Env file diff checker
Compare .env.example and local env keys to find missing and extra entries.
Inputs stay in your browser. Ignores comments and blank lines and reports duplicate keys.
Compares keys only; values are not retained, shown, or downloaded.
How to use this tool
Compare .env.example and local env keys to find missing and extra entries.
Prevent production deployment outages caused by missing environment variables. Compare `.env.example` templates against production `.env` files to find missing keys without leaking secrets.
💡 3 Quick Steps to Get Started
Paste your reference template on the left and target config on the right.
The tool extracts keys while ignoring sensitive secret values to detect omissions.
View a clear breakdown of missing, extraneous, or duplicate configuration keys.
When it helps
Compares keys only, not values, for pre-deploy checks.
How it works
Ignores comments and blank lines and reports duplicate keys.
Worked example
Example: check whether production misses API_URL or SECRET.
Limits and data handling
It does not validate values, runtime behavior, or whether a deployment will work.
No. The Env file diff checker runs in the browser. Do not paste production secrets or unredacted personal data.
The Twelve-Factor App Env Management & Secrets Diff Handbook
1. The Twelve-Factor App Configuration Methodology
The Twelve-Factor App design rules mandate strict separation of config from codebase. Modern cloud-native microservices maintain invariant compiled artifacts while dynamically ingesting environment variables across local dev, staging, and production clusters.
2. Multi-Environment Schema Synchronization & Outage Prevention
A primary driver of zero-day deployment outages is orphaned configuration keys missing from production runtime environments. Our diff utility parses key-value pairs, isolating missing variables, schema mismatches, and drift between environments.
3. Secrets Sanitization and Zero-Telemetry Privacy
Credentials, private keys, and connection strings execute exclusively in client-side volatile memory, preventing credential exposure vectors.
Feedback
How can we improve this tool?
Send a suggestion or bug report for this tool.
FAQ
What input does the Env file diff checker accept?
Paste two env texts containing KEY=value lines.
How does the Env file diff checker produce its result?
It ignores comments and blanks, compares keys only, and lists missing, extra, and duplicate entries.
What are the Env file diff checker limitations?
It does not validate values, runtime behavior, or whether a deployment will work.
Does the Env file diff checker upload data?
No. The Env file diff checker runs in the browser. Do not paste production secrets or unredacted personal data.
