Environment Variable Validator

The validator checks for: unquoted values containing spaces, duplicate key names, invalid characters in key names (keys must be A-Z, a-z, 0-9, underscore only), keys starting with a digit, lines missing the = sign, and the use of the export prefix (which is shell syntax, not standard .env format). Empty values are flagged as warnings.

Quote values that contain spaces, special characters, or that could be misinterpreted by the parser. Single quotes preserve the literal value ('value with spaces'). Double quotes allow variable interpolation ("$OTHER_VAR"). For simple alphanumeric values and URLs, quotes are optional but recommended for clarity. Most .env parsers (dotenv, godotenv, python-dotenv) handle both quoted and unquoted values.

No. All parsing and validation happens entirely in your browser. Your environment variables — including any secrets, API keys, or passwords — never leave your machine and are never stored or logged anywhere.

Different .env parsers handle duplicates differently. Most will use the last value, but some use the first. This can cause hard-to-debug issues where the wrong value is applied depending on which library or deployment environment loads the file. Always use unique keys to avoid ambiguity.

The standard .env format (popularized by dotenv) uses KEY=value pairs, one per line. Comments start with #. Values may optionally be wrapped in single or double quotes. Blank lines are ignored. Keys should be UPPER_CASE by convention (though case is technically allowed). The export prefix from shell scripts (export KEY=value) is NOT part of the standard format — remove it when using .env files with application libraries.