Free Developer Tool
Environment Variable Validator
Validate .env files for security risks, formatting errors, and duplicate keys. Diff two environments and generate sanitized .env.example files instantly. 100% Browser-Based
Use a secrets manager instead of .env for:
Issues Found
Parsed Variables
Click value to reveal| Line | Variable | Value | Status |
|---|
Generated .env.example
Comparison Results
| Variable | Env A | Env B | Status |
|---|
How to Use
1. Validate Mode
Paste your .env file and click Validate. Instantly see security risks, formatting errors, duplicate keys, and every parsed variable — masked by default.
2. Diff Mode
Compare two environments side by side — spot missing variables, value differences, and keys that exist in only one environment (e.g. dev vs prod).
3. Generate Example
After validating, click Generate .env.example to create a sanitized template: keys are preserved, actual values replaced with safe placeholders.
.env File Best Practices
Never Commit Secrets
Add .env to your .gitignore file. Commit a .env.example with placeholder values instead. Rotate any secrets accidentally committed immediately.
Use a Secrets Manager in Production
AWS Secrets Manager, HashiCorp Vault, Doppler, or 1Password Secrets Automation provide rotation, auditing, and access control that .env files cannot. Inject values at runtime instead.
Naming Conventions
Use UPPER_SNAKE_CASE for variable names, starting with a letter. Group related variables with shared prefixes like DB_, AWS_, or REDIS_.
100% Client-Side Privacy
All validation happens entirely in your browser using JavaScript. Your .env contents are never sent to any server. You can disconnect from the internet and this tool still works.
.env Format Reference
| Syntax | Description | Example |
|---|---|---|
| KEY=value | Unquoted value | PORT=3000 |
| KEY="value" | Double-quoted (allows spaces) | APP_NAME="My App" |
| KEY='value' | Single-quoted (literal) | REGEX='^[a-z]+' |
| export KEY=value | Shell export syntax | export NODE_ENV=production |
| # comment | Full-line comment | # Database config |
| KEY= | Empty value (flags a warning) | OPTIONAL_KEY= |
Common Use Cases
Security Audit
Find hardcoded secrets, AWS keys, connection strings with embedded passwords, and JWT tokens before they leak. Get recommendations for secrets manager migration.
Environment Sync
Diff your local .env against staging or production to find missing variables causing deployment failures. Color-coded table shows exactly what differs.
Onboarding Docs
Generate a clean .env.example with placeholder values in one click. Commit it to your repo so new developers know exactly which variables to set up.
Secure Your Configuration Pipeline
From secrets management to CI/CD automation — we build custom developer tooling, security auditing workflows, and internal platforms that keep your team shipping safely. Let us help you eliminate configuration drift and credential exposure.
Talk to Our Team