Free Developer Tools

Send REST API requests directly in your browser. Custom headers, JSON body, response inspection, and request history. No install needed.

Build and test HTTP requests visually. Generate cURL commands.

Generate realistic mock API responses with custom status codes, headers, and JSON body. Quick templates for 200, 401, 404, 429, 500 and more.

Build mock HTTP responses for testing. Set status code, headers, and body — export as curl command, Jest fetch mock, or MSW v2 handler.

Paste any raw HTTP response to format JSON body, inspect headers, and analyze status codes, CORS, caching, and rate-limit signals instantly.

Convert rate limits across req/s, req/min, req/hr. Calculate delay per worker, burst refill time, and get a Node.js throttle snippet.

Enter RPM limit and burst size to get token bucket config, per-worker request delay, refill time, and code snippets for Express.js, Nginx, and Cloudflare Workers.

Complete reference for all HTTP status codes with descriptions, use cases, and searchable index.

Browse all HTTP status codes with descriptions, use cases, and common response headers. Filter by 1xx–5xx category, search by code or keyword, and copy ready-to-use examples.

Search and filter all HTTP status codes (1xx–5xx). Shows category, description, common causes, usage guidance, and curl examples. Click any code for instant details.

Complete reference for GET, POST, PUT, PATCH, DELETE, HEAD, OPTIONS and more. Includes safe/idempotent/cacheable properties and real-world examples.

Inspect HTTP response headers for any URL. See security headers, cache directives, CORS settings, and more — with plain-English explanations for every header.

Test CORS headers for any URL. Analyze preflight responses and diagnose cross-origin errors.

Look up A, AAAA, CNAME, MX, TXT, NS, SOA, and PTR records for any domain using the Cloudflare DNS-over-HTTPS API. Fully client-side.

Check SSL/TLS certificate validity, expiry date, issuer, and Subject Alternative Names for any domain. Queries Certificate Transparency logs via crt.sh.

Look up the geographic location of any IPv4 or IPv6 address — city, country, timezone, ISP, and coordinates. Or detect your own IP.

Generate Leaflet.js map initialization code. Choose tile provider (OpenStreetMap, CartoDB, Mapbox), set center/zoom, add marker/circle/polygon layers. CDN and npm ES module output. React cleanup included.

Convert a time across multiple timezones at once. Live world clock, pick source timezone, add destinations, and copy results. No signup needed.

Generate HTTP request snippets for cURL, fetch, Axios, Python requests, Go, and PHP. Configure method, URL, headers, and body. One-click copy.

Build curl commands visually. Set HTTP method, URL, query params, headers, auth (Bearer, Basic, API key), request body, and options. Copy the ready-to-run command instantly.

Connect to any WebSocket server, send and receive messages in real time, and inspect the message log with timestamps and byte sizes. No install needed.

Visualize API endpoint response times as a color-coded heatmap. Green <100ms, yellow 100–300ms, orange 300–500ms, red >500ms. Shows avg, P95, and max latency. Runs in browser.

Execute GraphQL queries and mutations against any public API. Split editor with Query/Variables tabs, syntax-highlighted JSON response, and response time tracking. No install needed.

Build GraphQL queries visually from your schema SDL. Select root fields, pick sub-fields, add arguments, and generate query/mutation/subscription strings instantly. Supports nested types.

Upload or paste a HAR file to analyze HTTP request performance. See slowest requests, largest responses, error count, and timing waterfall. Filter by status code or content type.

Paste your OpenAPI 3.x spec (YAML or JSON) to validate structure, find missing required fields, detect duplicate paths, check operationIds, and get errors/warnings with path references.

Build an OpenAPI 3.0 YAML spec visually. Define API info, add endpoints with methods and parameters, export YAML or JSON — ready for Swagger UI, Redoc, and code generation tools.

Build a GraphQL SDL schema visually. Add types, fields, scalars, enums — auto-generates Query/Mutation stubs. Copy-ready for Apollo Server, GraphQL Yoga, and more.

Paste a raw HTTP request or JSON webhook payload to inspect headers, body, method, and generate a curl command. Interactive JSON tree view and auth header detection.

Validate your SMTP server configuration — host, port (25/465/587), TLS/STARTTLS, and credentials. Detects common issues like blocked ports and missing auth. Client-side simulation.

Validate YAML syntax and see errors by line number. Format with consistent indentation or convert YAML to JSON. Supports mappings, sequences, and nested structures.

Compare two YAML files side-by-side with highlighted differences. Three views: side-by-side, unified git-style diff, and semantic key-level comparison. Perfect for Kubernetes manifests and config files.

Paste JSON and auto-generate a JSON Schema. Supports Draft-07 and 2020-12. Detects formats like date-time, email, uuid, and uri. Runs in your browser.

Format, beautify, and validate JSON instantly. Choose indent size, minify to one line, or copy the result. Syntax errors highlighted live.

Advanced JSON formatter with JSONPath querying, minify/beautify, schema validation, and diff comparison. Handle complex JSON structures with ease.

Paste JSON and click any value to instantly get its JSONPath and jq path. Visual tree explorer with copy-to-clipboard. Great for debugging API responses.

Compare two JSON objects side-by-side. Highlight added, removed, and unchanged lines instantly. Perfect for debugging API responses.

Convert a JSON array to CSV format. Choose comma, tab, semicolon, or pipe delimiter. Download as .csv file. All processing client-side.

Convert CSV data to JSON. Supports comma, tab, semicolon, and pipe delimiters. Output array of objects (with headers) or array of arrays. Download as .json.

Edit CSV files directly in your browser. Inline cell editing, sort columns, filter rows, add/delete rows and columns, and export to CSV, TSV, or JSON.

Paste CSV data and instantly preview it as a formatted table. Supports multiple delimiters, quoted fields, and toggleable header rows.

Format messy XML with clean indentation or minify it to reduce size. Invalid XML is caught instantly with a clear error message.

Paste XML and get clean JSON output. Attributes become @-prefixed keys, repeated elements become arrays, and booleans/numbers are auto-cast. Free, runs in your browser.

Convert between JSON and YAML formats. Handles nested objects, arrays, and all scalar types. Useful for config file migration.

Validate TOML syntax and see the parsed result as JSON. Useful for Cargo.toml, pyproject.toml, and other TOML config files.

Generate Apache Avro schema definitions from JSON sample data. Detects nested records, arrays, nullable fields, and logical types (timestamp-millis, date). Useful for Kafka + Schema Registry.

Validate Protocol Buffer .proto files for syntax and compatibility. Catches missing syntax declarations, duplicate field numbers, naming convention violations, and proto3 rules. Runs in browser.

Paste JSON and get TypeScript interfaces instantly. Handles nested objects, arrays, optional fields, and custom root names. Runs entirely in your browser.

Format and indent SQL queries automatically. Uppercase keywords, align clauses, and minify SQL to one line. Supports SELECT, JOIN, CTEs, and more.

Build type-safe SQL queries with Kysely TypeScript query builder. Select columns with aggregates, add WHERE/JOIN/ORDER BY, configure pagination, and get Kysely code + TypeScript Database interface. Runs in browser.

Convert JSON Schema (Draft-07, 2020-12) to Zod TypeScript validation code. Supports objects, arrays, enums, required/optional fields, min/max constraints, and inferred TypeScript types.

Build schema.prisma files visually. Add models and fields, configure types, @id, @default, @unique, @updatedAt. Generates copy-ready Prisma ORM schema for PostgreSQL, MySQL, SQLite, and more.

Build Neon serverless PostgreSQL connection strings for pooled and direct modes. Generates .env values, Prisma datasource, @neondatabase/serverless, and Drizzle ORM setup code.

Paste any MySQL query and get a plain-English explanation of each execution step plus optimization hints. Covers SELECT, JOIN, GROUP BY, UPDATE, DELETE, and CREATE TABLE.

Paste EXPLAIN or EXPLAIN ANALYZE output and get a visual cost breakdown per node, optimization suggestions, and actual vs estimated row counts.

Convert TOML to JSON or JSON to TOML instantly. Supports sections, key-value pairs, arrays, booleans, and all scalar types. Bidirectional. Runs in your browser.

Format messy HTML with proper indentation or minify to reduce file size. Handles void elements, pre/script blocks, and nested tags. Runs in your browser.

Beautify CSS with consistent indentation or minify to strip whitespace. Supports @media, @keyframes, nested rules. Shows compression savings.

Strip comments, whitespace, and redundant characters from CSS. Shows original size, minified size, and exact % saved. Runs entirely in your browser.

Format JS for readability or minify to reduce bundle size. Preserves strings and template literals. Works with JS, TS, and JSX.

Strip TypeScript type annotations, interfaces, generics, enums, access modifiers, and decorators to get clean JavaScript. Runs in your browser.

Decode JWT tokens — inspect header, payload, and claims. Check expiry and iat/sub/iss fields instantly.

Create HS256 JWT tokens with custom header, payload claims, and secret key. Color-coded output. Great for testing auth flows.

Generate RSA-OAEP key pairs (2048 or 4096-bit) in your browser. Export public and private keys in PEM format. Uses Web Crypto API.

Toggle and configure HTTP security headers (HSTS, CSP, X-Frame-Options). Generates ready-to-use nginx and Apache configuration snippets.

Generate MD5, SHA-1, SHA-256, and SHA-512 hashes instantly. All hashing runs in your browser — nothing sent to any server.

Generate cryptographically secure random passwords with custom length and character sets. No data sent to any server.

Test any password instantly — strength score, entropy estimate, criteria checklist, and improvement tips. Nothing is stored or sent anywhere.

Generate .htpasswd entries for Apache and Nginx Basic Auth. Supports bcrypt (apr1), SHA-1, and plain formats. All hashing runs in your browser — no data sent to servers.

Generate diceware-style passphrases with crypto.getRandomValues(). Configure word count (3–8), separator, capitalization, and number suffix. Shows entropy strength. Fully client-side.

Generate HMAC-SHA256, HMAC-SHA512, and HMAC-SHA1 hashes. Enter message and secret key, choose hex or base64 output. Uses Web Crypto API — runs entirely in your browser. For JWT signing, webhook verification.

Build Content Security Policy headers visually. Toggle directives (default-src, script-src, img-src, etc.), set allowed sources, and get nginx/Apache config snippets. Defends against XSS attacks.

Generate bcrypt password hashes with a configurable cost factor (4–14) and verify passwords against existing hashes. Shows full hash breakdown (version, cost, salt). Runs in your browser using bcryptjs.

Generate Clerk authentication configuration for Next.js, Remix, and Astro. Configure protected routes, social OAuth providers (Google, GitHub, Discord), middleware.ts, and .env variables. Copy-ready output.

Encrypt and decrypt text using AES-256-GCM in your browser. Key derived via PBKDF2-SHA256 with 100,000 iterations. No data sent to any server — fully client-side using Web Crypto API.

Decode X.509 / SSL / TLS certificates from PEM format. View subject, issuer, SANs, expiry (color-coded), key usage, and SHA-256 fingerprint. Runs entirely in your browser — no uploads.

Generate TOTP one-time codes from a Base32 secret. Compatible with Google Authenticator, Authy, and all RFC 6238 apps. Live countdown timer and next-code preview. Secret stays in your browser.

Write TypeScript and instantly see compiled JavaScript output. Strip interfaces, generics, enums, and decorators. Share code via URL. No install needed.

Write and test regular expressions in real-time with match highlighting, flag toggles (g, i, m, s), and group display. Instant feedback as you type. No install needed.

Test your regular expressions against multiple strings at once. Batch validate with pass/fail assertions and match highlights. Free, no signup.

Advanced regex tester with real-time match highlighting, multiple language flavors (JS/Python/Ruby), 6 presets, and capture group display. Visual regex debugging.

Build cron expressions visually with common presets. See next run times in plain English. Copy for GitHub Actions, Linux crontab, AWS EventBridge. Free, no signup.

Build and validate cron expressions visually. See next 5 run times in plain English with common presets for hourly, daily, and weekly jobs.

Validate cron expressions and see a human-readable schedule with the next 5 run times. Field-by-field breakdown and common presets included.

Parse and decode cron expressions instantly. Plain-English description, field-by-field breakdown, and next 5 scheduled run times. Works with Linux, GitHub Actions, and AWS EventBridge.

Visualize cron expressions with a plain-English description, field-by-field breakdown, and next 5 scheduled run times preview. Common presets included. Free, runs in your browser.

Test any cron expression and see the next 10 scheduled run times with a plain-English explanation of each field. Works with Linux cron, GitHub Actions, and POSIX schedules.

Build Git commands step by step: clone, branch, merge, rebase, reset, stash, and more. Shows all relevant flags with descriptions. Copy the final command instantly.

Generate clean commit messages following the Conventional Commits spec. Pick type, scope, description, body, and issue references. Copy in one click.

Describe your change in plain English and get commit message suggestions — Conventional Commits, imperative, and bracket-style. Auto-detects type and scope.

Interactive wizard to generate production-ready Dockerfiles for Node.js, Python, Go, Java, and Rust. Multi-stage builds, port config, custom layers.

Generate docker-compose.yml visually. Add services, configure ports, volumes, environment variables, and depends_on. Templates for web + db, full-stack, and microservices setups.

Paste your docker-compose.yml and validate it instantly. Catches missing image/build, broken depends_on, hardcoded secrets, :latest tags, and YAML errors.

Parse .env and docker-compose env_file format. See key-value table, detect duplicate keys and missing values, export as docker run --env flags or shell export statements.

Parse, compare, and check semantic version ranges. Verify ^, ~, >= constraints, compare two versions, or calculate the next major/minor/patch bump.

Enter a semver and click major, minor, patch, or pre-release to get the next version. Live preview of all bump types, bump history, configurable pre-release tags, and one-click copy.

Parse and validate .env files. Detect syntax errors, browse variables, generate a keys-only template, and export shell export commands. Fully client-side.

Generate .gitignore files for Node.js, Python, React, Java, Go, Rust, .NET, and Docker. Select extras like VS Code, macOS, Windows. Download instantly.

Paste your package.json to validate syntax and get an audit score. Detects wildcard versions, missing fields, misplaced dependencies, and more.

Paste code and get a shareable URL instantly. Encoded in the URL — no server, no sign-up, no expiry. Share on Slack, Discord, or email.

Generate GitHub Actions YAML workflows instantly. Choose triggers, runtime (Node.js, Python, Go, Rust), and jobs (test, lint, build, Docker). Copy-ready CI/CD YAML with best practices.

Calculate CPU/memory requests and limits for Kubernetes pods. Configure millicores, Mi/Gi memory, HPA replicas, and get ready-to-paste Pod spec YAML with resource quotas.

Generate Terraform variable declarations and tfvars files. Define variable name, type, default, and description — get complete variables.tf and terraform.tfvars output.

Build AWS IAM policies visually. Pick Effect, select Actions from S3/EC2/Lambda/DynamoDB service groups, enter Resource ARNs, and get a complete JSON policy document.

Validate GitHub Actions and GitLab CI YAML pipelines. Detects hardcoded secrets, mutable :latest image tags, deprecated syntax, and security best practices. Free, runs in browser.

Validate your GitHub Actions workflow YAML. Checks structure, trigger events, job dependencies, action version pins, hardcoded secrets, and cron expressions. Runs in browser.

Validate Ansible YAML playbooks for syntax and best practice issues. Catches hardcoded secrets, non-idempotent modules, missing task names, ignore_errors usage, and more. Runs in browser.

Generate RabbitMQ exchange, queue, and binding configurations in JSON or YAML. Configure exchange types (direct/topic/fanout/headers), TTL, max-length, dead letter exchanges, and routing keys.

Generate HashiCorp Vault HCL policy files visually. Configure paths, capabilities (create/read/update/delete/list/sudo/deny), with presets for read-only, app service accounts, PKI, and DB credentials.

Scaffold Temporal workflow and activity boilerplate for TypeScript, Go, or Python. Configure task queues, retry policies, signals, and queries. Outputs complete worker and client files.

Generate production-ready nginx server blocks. Supports static sites, reverse proxy, PHP-FPM, HTTPS redirects, SSL/TLS, gzip, cache headers, and security headers.

Generate Apache .htaccess configuration visually. Presets for SPA routing, WordPress, HTTPS redirects, gzip, browser caching, and security headers. Copy-ready output.

Calculate Unix/Linux file permissions visually. Toggle read/write/execute bits and instantly get octal (755), symbolic (rwxr-xr-x), and the chmod command.

Calculate IPv4 subnet details from CIDR notation. Get network address, subnet mask, broadcast, host range, and total usable hosts. Binary breakdown included.

Advanced IPv4/IPv6 subnet calculator. Supports variable-length subnet masking (VLSM), splits supernets into subnets, and shows all subnet properties: network, broadcast, gateway, and host range.

Build a valid robots.txt file visually. Add user-agent rules, disallow/allow paths, crawl-delay, and sitemap URL. Block AI crawlers preset included. One-click copy.

Build a valid XML sitemap. Add URLs with priority, change frequency, and last-modified date. Bulk import URLs. Copy XML or download sitemap.xml. Runs in your browser.

Generate ~/.ssh/config entries visually. Set host alias, hostname, user, port, identity file, ProxyJump, and ForwardAgent. Templates for AWS EC2, GitHub, and jump hosts.

Run Redis commands in your browser — SET, GET, HSET, LPUSH, EXPIRE, TTL, KEYS, and more. In-memory Redis playground with command history. No install needed.

Paste log output and filter by level: DEBUG, INFO, WARN, ERROR, FATAL. Color-coded highlights per level, search/grep within logs. Supports Log4j, Winston, Pino, Python logging.

Compare log levels across Winston, Pino, Python logging, Log4j, syslog, Go slog, and Ruby Logger. Severity mapping table and visual hierarchy — quickly find equivalents when switching frameworks.

Validate and parse Sentry DSN URLs. Extract public key, host, org ID, and project ID. Get SDK configuration examples for JavaScript, Node.js, Python, and React.

Format and validate Datadog key:value tags. Checks naming rules, warns about high-cardinality keys, and outputs formatted tags as a list, JSON array, Agent config YAML, and Python SDK snippet.

Generate OpenTelemetry Collector YAML config for common exporters (Jaeger, Zipkin, Prometheus, OTLP). Select receivers, processors, and exporters to build a production-ready otel-collector.yaml.

Estimate API costs for GPT-4o, Claude 3.5, Gemini 1.5, and more. Enter token counts, character count, or word count and get instant per-call and monthly projections.

Paste text to count approximate tokens and estimate API costs for GPT-4o, Claude 3.5, Gemini 1.5, and more. Configure output tokens and monthly volume for accurate projections.

Calculate OpenAI API costs for GPT-4o, GPT-4 Turbo, GPT-3.5, o1, and o3 Mini. Enter input/output tokens and monthly request volume for side-by-side cost comparison.

Count tokens for GPT-4o, GPT-4 Turbo, and GPT-3.5 Turbo prompts. Uses cl100k_base / o200k_base estimation. Live token count, character count, word count, cost estimate, and context window usage bar.

Generate LangChain Python code for LLMChain, SequentialChain, or LCEL pipe chains. Pick model (GPT-4o, Claude, Gemini), set temperature and max tokens, define prompt templates with {variable} placeholders.

Browse and compare Ollama local LLM models. Filter by Chat, Code, Vision, and Embedding categories. See param count, context window, and use case. Copy ollama pull commands instantly.

Compare monthly API costs across GPT-4o, Claude Sonnet, Gemini Pro, and 12+ models. Enter daily requests and token counts to find the most cost-effective model for your workload.

Build reusable AI prompt templates with {slot} variables. Fill values, preview the finished prompt, and export as JSON. Works with ChatGPT, Claude, and Gemini.

Build reusable prompt templates with {{variable}} placeholders. Auto-detects variables, fills them interactively, previews the complete prompt, and exports as JSON. Works with ChatGPT, Claude, and Gemini.

Paste any function or class and get complete unit tests — happy paths, edge cases, and error handling. Supports Jest, Vitest, pytest, and more. Pro feature.

Paste any stack trace or error message and get a plain-English explanation plus step-by-step fix instructions. Pro feature.

Paste any regular expression and get a part-by-part breakdown in plain English, match examples, and gotcha warnings. Pro feature.

Self-healing monitoring daemon for multi-agent AI systems. 21-pattern deep code scanner, 13 runtime health checks, auto-restart, pipeline stall recovery, and budget alerts.

Describe what your variable or function should represent in plain English and get naming suggestions in camelCase, snake_case, PascalCase, SCREAMING_SNAKE, and more. Runs in your browser.

Enter your branch name and commit messages to generate a complete pull request description with summary, change type, change list, and testing checklist. Works with GitHub, GitLab, and Bitbucket.

Paste any function or class signature and get a complete JSDoc, TSDoc, Python docstring, or Rust doc comment generated instantly. Parses param types and return types automatically.

Focus timer using the Pomodoro Technique. 25/5/15-minute intervals, sound notifications, session counter. Works offline, no signup needed.

Countdown by duration (5 min, 30 min, custom) or to a specific date and time. Great for meetings, deadlines, and sprints. Works offline.

Build PostHog analytics event tracking schema visually. Define events with typed properties, add person properties, and generate posthog.capture() code for Browser JS, Node.js, and Python. TypeScript interfaces included.

Generate D3.js v7 chart code with live SVG preview. Select bar, line, area, pie, or scatter chart. Input CSV or JSON data, configure colors and labels. Copy-ready D3 code for React and plain HTML.

Live GLSL WebGL fragment shader editor with real-time canvas preview. Write shaders with u_time, u_resolution, and u_mouse uniforms. 4 starter templates: gradient, wave, noise, interactive circle.

Write HTML with Tailwind CSS utility classes and see a live split-pane preview instantly. 4 starter templates (Card, Flex, Form, Hero). Powered by Tailwind CDN. No install needed.

Generate SEO, Open Graph, and Twitter Card meta tags with a live social preview. Copy all tags in one click. No signup required.

Preview how your page looks when shared on X/Twitter, Facebook, and Slack. Edit og:title, og:image, og:description and copy all meta tags in one click.

Generate structured data JSON-LD markup for SEO. Supports Article, Product, Organization, FAQ, and BreadcrumbList schemas. Live preview with copy button. Runs in your browser.

Preview Twitter/X Card meta tags before publishing. Configure card type (summary/summary_large_image), title, description, and image. Live visual preview + copy-ready meta tags HTML.

Build multi-layer CSS box-shadow values visually with live preview. Presets, inset, blur, spread, opacity, and one-click copy.

Build linear, radial, and conic CSS gradients visually. Add color stops, adjust angles, and copy the ready-to-use CSS instantly.

Interactive flexbox playground. Set flex-direction, justify-content, align-items, flex-wrap, and per-item grow/shrink/basis — with a live preview and copy-ready CSS output.

Build CSS Grid layouts visually. Set columns, rows, gaps, and alignment — click items to control placement. Copy generated CSS in one click.

Convert between px, rem, em, vw, vh, pt, and % instantly. Configure base font size, viewport, and parent size for accurate relative unit calculations.

Build CSS keyframe animations with live preview. 10 presets (fade, bounce, shake, spin), configure timing, easing, delay. Copy ready-to-use CSS.

Pick a color and instantly get HEX, RGB, HSL values. WCAG contrast checker and 5-shade palette generator.

Convert colors between HEX, RGB, and HSL formats instantly. Type in any field and all formats update automatically. Visual picker and presets included.

Generate full palettes from any hex color — Tailwind-style shades, complementary, triadic, analogous, and tetradic. Export as CSS custom properties.

Preview how colors look with protanopia, deuteranopia, tritanopia, and achromatopsia. Essential for accessible design. Simulates 5 vision types.

Format any number in 15+ ways: US/EU locale, currencies (USD/EUR/GBP/JPY), scientific notation, binary, hex, octal, words, and file sizes.

Check foreground/background color contrast ratios against WCAG 2.1 AA and AAA standards. Instant pass/fail results with suggested fixes.

Calculate simplified aspect ratios, scale dimensions proportionally, and find common screen sizes for any width/height pair. Includes CSS padding-top value.

Build CSS border-radius values visually. Control all four corners individually, use elliptical radii for organic shapes, or pick from 12 presets.

Calculate CSS selector specificity in (inline, ID, class, element) notation. Compare two selectors to see which wins the cascade. All logic runs in your browser.

Calculate and compare CSS selector specificity as (inline, ID, class, element) notation. Supports :not(), :is(), :has(), :where(), attribute selectors, and pseudo-elements. With FAQ and schema markup.

Paste, preview, format, and optimize SVG code in your browser. Removes comments, collapses whitespace, shortens hex colors, and reduces file size. Export as data URI.

Optimize and minify SVG files in your browser. Removes comments, metadata, editor data, and whitespace. Typically reduces SVG size by 30-70%. Free, 100% client-side.

Edit SVG path d attributes visually. Drag control points and Bézier handles on a live canvas. Supports M, L, C, Q, Z commands. Copy the d attribute output instantly.

Generate CSS clip-path shapes visually. 16 polygon presets (triangle, star, hexagon, arrow), plus circle, ellipse, and inset modes. Live preview and one-click copy.

Encode and decode Base64 strings online. Supports UTF-8 text, URL-safe encoding, and binary data. Runs in your browser.

Advanced Base64 tool supporting text, image, and file encoding. URL-safe mode, data URI generation, and instant preview. No file size limits.

Encode text to percent-encoded URL format or decode %20 / %3D / %2F sequences back to readable text. Full URL mode supported.

Encode special characters to HTML entities (&lt; &gt; &amp;) or decode entities back to plain text. Supports 50+ named entities.

Convert text between camelCase, PascalCase, snake_case, kebab-case, SCREAMING_SNAKE, Title Case, dot.case, and 5 more formats.

Create GitHub-Flavored Markdown tables visually. Set rows, columns, and per-column alignment (left/center/right). Auto-pads output. Import existing tables to edit.

Write and preview Markdown in real-time. Supports GFM tables, task lists, and code blocks with syntax hints.

Compare two code snippets with unified or split side-by-side view. Highlights added/removed lines, shows change counts. Runs in your browser.

Compare two text blocks side-by-side with line-level diff highlighting. Lines added, removed, and unchanged at a glance.

Count words, characters, sentences, paragraphs, and lines. Get reading time estimate and top word frequency. Works on any text instantly.

Sort lines A–Z, by length, reverse, or shuffle. Remove duplicates, trim whitespace, and delete empty lines. Perfect for cleaning lists and configs.

Convert HTML to Markdown. Handles headings, bold, italic, links, images, lists, tables, code blocks, and blockquotes. Side-by-side view.

Convert Markdown to clean HTML with a live preview tab. Supports headings, bold, italic, code blocks, lists, links, blockquotes, and strikethrough.

Generate TOTP codes from a Base32 secret. Live countdown timer, next-code preview. RFC 6238 compatible with Google Authenticator, Authy, and Microsoft Authenticator.

Convert between plain text, binary, and hexadecimal. Choose separator, instant conversion, handles ASCII. 4 modes: text↔binary, text↔hex.

Parse any URL into protocol, hostname, port, path, query parameters, and hash. Or build a URL from parts in the builder mode.

Look up any Unicode character by typing it, U+XXXX code point, decimal, or HTML entity. Get UTF-8 bytes, UTF-16, HTML entities, CSS and JS escape sequences instantly.

Convert any text into ASCII art instantly. Choose from Classic, Blocks, Simple, and Bold styles. Copy and share — runs entirely in your browser.

Calculate your exact age in years, months, and days. See next birthday countdown, day of week born, Chinese zodiac, and Western zodiac sign.

Create .ics calendar event files with title, time, location, organizer, and repeat rules. Compatible with Google Calendar, Outlook, and Apple Calendar.

Convert between Unix timestamps and human-readable dates. Live clock, timezone support, and instant copy.

Convert between binary, octal, decimal, and hexadecimal instantly. Enter any value in any base — all others update automatically.

Generate UUID v1, v4, and v5 in bulk. Multiple formats: standard, uppercase, no-hyphens, braces. One-click copy.

Generate UUID v7 — the timestamp-ordered UUID format from RFC 9562. Sortable, database-friendly, ideal for distributed systems. Also generates UUID v4, ULID, and nanoid.

Generate 1 to 1,000 UUIDs at once. Choose v1, v4, v5, or v7. Uppercase or lowercase, with or without hyphens. Copy all or download as .txt. No signup required.

Generate deterministic UUID v3 (MD5) and v5 (SHA-1) from a namespace and name. DNS, URL, OID, X500 presets or custom namespace. Batch up to 100 names. Runs in your browser.

Convert any title or text into a clean URL-safe slug. Handles accented characters, camelCase, and special characters. Choose hyphen, underscore, or no separator.

Generate realistic fake user records — names, emails, phones, addresses — in JSON, CSV, or SQL INSERT format. 3 locales (en/zh-TW/ja), 1–100 records.

Generate Lorem Ipsum placeholder text — paragraphs, sentences, or words. Start with the classic opening line. Instant copy for mockups and wireframes.

Generate QR codes for URLs, WiFi, email, phone, and more. Custom colors, error correction levels, PNG download. No signup, no watermark.

Convert PNG, JPG, SVG, WebP images to Base64. Get the data URL or CSS background-image value. Drag-and-drop, runs entirely in your browser.

Estimate software engineer salary ranges by role, location, and experience level. Covers SF, NYC, Seattle, Remote, London, Berlin, Toronto, and more. No signup.

Interactive reference for system design interviews: CAP theorem, load balancers, caching, database types, message queues, consistent hashing, CDNs, and more.

Describe your coding problem and instantly surface the matching algorithm pattern — Two Pointers, Sliding Window, BFS, DP, Heap, Trie, Union-Find — with code templates.

Generate strong, quantified resume bullet points in STAR format for software engineering roles. 6 achievement templates: built, optimized, led, automated, and more.

Curated interview questions with hints for React, Node.js, Python, Go, TypeScript, SQL, System Design, and Behavioral rounds. Filter by difficulty and type.

40+ items to build a software engineer portfolio that gets you hired. Foundation, projects, GitHub, SEO, contact. Progress saved in your browser.

Paste your resume text and get an instant score with actionable feedback. Checks contact info, action verbs, metrics, tech keywords, and structure.

Build an ATS-optimized developer resume section by section. Add experience with impact-driven bullets, projects, skills, and education. Export to Markdown or JSON.

Generate an embeddable SVG card showing your GitHub repos, total stars, followers, and top languages. Paste into your README — viral loop guaranteed.

Paste a GitHub repo URL to instantly detect its tech stack — languages, frameworks, databases, testing tools, and DevOps setup. Creates a shareable stack report.

Fill in project details and generate a complete README.md with badges, table of contents, features, installation steps, and contributing guide. Download instantly.

Generate a valid Web App Manifest (manifest.json) for your PWA. Configure name, icons, display mode, theme colors, and orientation. Download ready-to-use JSON.

Generate a ready-to-use service worker (sw.js). Choose cache strategy — Cache First, Network First, or Stale While Revalidate. Configure URLs to cache and download.

Enter LCP, INP, and CLS values to get instant Pass/Fail ratings against Google Core Web Vitals thresholds with optimization tips for each metric.

Learn LCP, INP, and CLS with interactive explanations and a score simulator. Enter your metric values to get Pass/Fail ratings and targeted optimization tips.

Enter your LCP, INP, and CLS scores to get instant pass/fail grades with color-coded results and improvement recommendations. Also supports FCP and TTFB.

Enter image dimensions and file size to get format recommendations, compression targets, srcset breakpoints, lazy loading guidance, and CDN tips.

Estimate how much file size you'll save by converting images to WebP or AVIF. Get bandwidth savings and LCP improvement estimates based on industry compression ratios.

Paste HTTP response headers to get plain-English explanations. Identifies security headers, cache directives, CORS policies, and flags missing critical headers.

Preview how your page appears when shared on Twitter/X, Facebook, and LinkedIn. Configure og:title, og:description, og:image, and twitter:card with live social previews.

Validate your sitemap.xml structure, namespace, URL count, and required fields. Flags common SEO mistakes that prevent Google from reading your sitemap.