Complete Guide to .env Files for Configuration
How to use .env files for configuration, best practices, and common patterns.
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ENV File Converter
Data FormatsConvert .env files to JSON and back
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2 articles to help you understand and use this tool effectively
ENV File Converter FAQ
Common questions about using the ENV File Converter tool
A .env file stores environment variables as KEY=value pairs, one per line. Used to configure applications without hardcoding values. Common for: API keys, database URLs, feature flags. Never commit secrets to version control.
Paste your .env content in the input, select 'ENV to JSON'. Each KEY=value becomes a JSON property. Useful for: config management, programmatic access, API payloads. The tool handles quotes and special characters.
Paste JSON object in input, select 'JSON to ENV'. Properties become KEY=value lines. Nested objects are flattened or serialized. Useful for generating .env files from config objects or API responses.
Wrap values with special characters in quotes: KEY="value with spaces". For quotes within values, escape them: KEY="value with \"quotes\"". Newlines: use \n or multiline with quotes. The tool handles escaping automatically.
Never commit .env files with secrets. Add .env to .gitignore. Instead: 1) Provide .env.example with placeholder values, 2) Document required variables, 3) Use secret management (Vault, AWS Secrets) in production.
Access with process.env.VARIABLE_NAME. Use dotenv package to load .env files: require('dotenv').config() at app start. For TypeScript, add types. Modern frameworks (Next.js, Vite) have built-in .env support.
Conventions vary by framework. Common pattern: .env (shared defaults), .env.local (local overrides, gitignored), .env.production (production values). Load order typically: .env → .env.local → .env.[environment].
Use libraries like envalid (Node.js) or python-dotenv with validation. Check required variables exist at startup, validate formats (URLs, numbers), provide defaults where appropriate. Fail fast if critical vars are missing.
Yes, use quotes: KEY="line1\nline2" or KEY="line1 line2" (actual newline within quotes). Support varies by parser. For complex multiline content, consider Base64 encoding or external config files.
Options: 1) Platform environment settings (Vercel, Heroku), 2) Secret managers (AWS Secrets, HashiCorp Vault), 3) Kubernetes secrets/configmaps, 4) CI/CD variables. Never use .env files in production containers.