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Free ENV File Validator

Lint a .env file for duplicate keys, bad spacing, and unquoted values — then get a cleaned, sorted version and a ready-to-commit .env.example. Runs in your browser.

Works offline once loaded

💡 Catches duplicate keys, spaces around =, unquoted values, and naming-convention issues — then gives you a cleaned, sorted file and a ready-to-commit .env.example. Your secrets are parsed entirely in your browser and never uploaded.

Common uses

  • Generate a .env.exampleCreate a .env.example from your real .env so teammates know what to set.
  • Debug a Broken .env FileFind why your environment variables aren't loading.
  • Clean Up a Messy .envSort, de-duplicate, and normalise an .env file.
  • Enforce .env Naming ConventionsCheck that environment variable names follow UPPER_SNAKE_CASE.
  • Validate .env Before DeployingCatch config mistakes before they reach production.

How It Works

A malformed .env file causes confusing config bugs — a duplicate key, a stray space around "=", an unquoted value with a space. This lints your file and cleans it up, all locally (important, since .env files hold secrets).

  1. 1
    You paste your .env
    Each line is parsed: comments and blanks are skipped, "export" prefixes handled.
  2. 2
    It checks for problems
    Duplicate keys, spaces around "=", invalid key names, non-uppercase keys, empty values, and unquoted values containing spaces or "#" are flagged with line numbers.
  3. 3
    It produces a cleaned file
    Keys are de-duplicated (last value wins), sorted alphabetically, and values are quoted where needed.
  4. 4
    And a .env.example
    The same keys with blank values — ready to commit so teammates know which variables to set, without leaking secrets.

.env files are full of secrets — API keys, database passwords. This tool parses everything in your browser and never uploads a thing, so it's safe to paste a real file.

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Frequently Asked Questions