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.env File Validator & Converter

FREEDeveloper
TOOL.env File Validator & Converter
100% freeNo signupRuns in your browser

About .env File Validator & Converter

.env files are the de facto standard for managing environment-specific configuration in twelve-factor applications. The dotenv convention — popularized by Heroku and the dotenv npm package — uses KEY=VALUE pairs with support for comments, quoted values, and multi-line strings. In practice, .env files accumulate errors over time: duplicate keys, values with unquoted spaces that break parsers, undocumented secrets left out of .env.example, and format drift between team members. Converting .env to Kubernetes ConfigMap YAML or Docker --env-file format by hand is tedious and error-prone.

How It Works

The parser reads .env content line by line, skipping blank lines and lines beginning with #. Each non-comment line is split on the first = character. The key is trimmed of whitespace; the value is unquoted (stripping surrounding single or double quotes), and multi-line quoted values are collapsed. Validation rules check for duplicate keys (same key appearing twice), empty values (key= with nothing after the equals sign), values containing spaces that are unquoted, and keys that do not match the conventional ALL_CAPS_UNDERSCORE naming pattern.

Secret detection compares each key against a list of sensitive patterns (PASSWORD, SECRET, TOKEN, API_KEY, PRIVATE_KEY, AUTH, CREDENTIAL, CERT, PWD) using a case-insensitive substring match. Detected keys are highlighted with a warning indicator but are not redacted — the tool never modifies your input.

Conversion to Kubernetes ConfigMap generates a YAML manifest with the data field containing all key-value pairs. Docker --env-file format strips quotes and exports bare KEY=VALUE lines compatible with docker run --env-file.

Who Is This For

A developer onboarding to a new project compares their local .env against the committed .env.example to find the three missing API keys blocking their dev server.

A DevOps engineer converts an application's .env file to a Kubernetes ConfigMap manifest as part of a containerization migration, saving 20 minutes of manual YAML writing.

A tech lead runs the validator on a PR diff to catch a duplicate DATABASE_URL key before it reaches staging and causes a silent connection failure.

A developer generates a sanitized .env.example from a production .env before open-sourcing a project, ensuring no credentials are accidentally committed.

Scope note: Avoid pasting .env files containing production secrets in shared or public environments. Although all processing happens in your browser and no data is uploaded, screen-sharing or browser history could expose sensitive values. For production secret management, use a dedicated secrets manager (AWS Secrets Manager, HashiCorp Vault, Doppler) rather than browser-based tools.

How to Use

1

Paste your .env file content in the input panel

2

Choose a mode — Validate, Compare, Convert, or Generate Example

3

In Convert mode, pick the target format (JSON, YAML, Docker, Kubernetes)

4

Copy the output or review validation warnings and secret detections

Frequently Asked Questions

It checks for duplicate keys, empty values, missing quotes around values with spaces, invalid line format, and highlights potential secrets (keys with PASSWORD, SECRET, TOKEN, API_KEY).
.env to JSON, YAML, Docker --env-file format, and Kubernetes ConfigMap YAML. Reverse conversion from JSON/YAML back to .env is also supported.
It strips all values from your .env and keeps only the keys with empty values or placeholder comments, creating a safe .env.example file to commit to version control.
Yes. Everything runs in your browser. No data is uploaded to any server.
The tool highlights values where the key name contains common secret indicators (PASSWORD, SECRET, TOKEN, API_KEY, PRIVATE_KEY, AUTH, CREDENTIAL). It does not scan value content for entropy patterns. Think of it as a naming-convention check, not a full secret scanner — for comprehensive scanning use tools like truffleHog or gitleaks in CI.
Paste your actual .env in the left panel and your .env.example in the right panel. The tool identifies keys present in .env.example but missing from your .env (onboarding blockers) and keys in your .env not documented in .env.example (documentation gaps). Both lists are shown with copy buttons for quick remediation.
The output includes a minimal ConfigMap manifest with apiVersion, kind, metadata (name placeholder), and data fields. Replace the name placeholder with your actual ConfigMap name before applying with kubectl. Sensitive values should be moved to a Secret object rather than a ConfigMap.

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