DevOps
Env File Linter
Paste a .env file to surface warnings for duplicates, empty values, and unsafe names.
The Env File Linter scans a `.env` file for common configuration issues such as duplicate keys, empty values, or keys with unsafe naming patterns. It surfaces warnings so you can clean up environment files before they reach production, reducing the chance of silent configuration bugs.
Warnings only. No AI. Runs entirely in your browser.
Paste .env
Each warning highlights a key that should be fixed.
What this tool does
The Env File Linter scans a `.env` file for common configuration issues such as duplicate keys, empty values, or keys with unsafe naming patterns. It surfaces warnings so you can clean up environment files before they reach production, reducing the chance of silent configuration bugs.
When to use this tool
Use it when onboarding a new project, reviewing a shared `.env` template, or troubleshooting confusing runtime behavior. It is also a good check before sharing configuration with teammates. If you need to summarize config changes for non-technical stakeholders, pair this with Human Readable Config.
How it works
The linter reads each line, extracts key/value pairs, and flags duplicates or missing values. It also checks for keys that use inconsistent casing or contain unsafe characters. Results are presented as warnings only so you remain in control of how strict to be for your environment.
Example use case
Your team has merged configuration from multiple services and the app now reads the wrong `API_URL`. Paste the `.env` file and the linter highlights duplicate keys. You remove the outdated entry, rerun the tool, and ship a clean configuration with a single source of truth.
Use cases
- Review a .env file before deploying a new service.
- Clean up an onboarding template shared across teams.
- Detect duplicate keys after merging configuration files.
Notes & limitations
This linter does not validate whether values are correct, only whether keys look suspicious or empty. It cannot check secrets against external services. Always verify sensitive values in your deployment pipeline. The tool operates locally in your browser; do not paste secrets if you are on an untrusted device.
Comments and quoted values are supported for basic cases, but unusual formatting may not parse as expected. Keep `.env` files simple and consistent, and prefer `.env.example` templates to document required keys without exposing real values.
If you use multiline secrets, store them outside `.env` files and reference them securely instead.
Keep a short changelog when keys are renamed.
