.env linter
Paste a dotenv file. Find duplicate keys, empty names, bad lines, and risky spacing. Nothing is uploaded.
Ready
How it works
Dotenv files are usually KEY=VALUE lines, # comments, and blank lines. Values may be quoted. Some runtimes allow optional export prefixes.
This linter does not execute the file or talk to a server. It flags structural problems: missing keys, duplicates, spaces around =, empty keys, and non-assignment lines.
It never “fixes” secrets or validates that a token is real — only shape.
Examples
DATABASE_URL=postgres://localhost:5432/app NODE_ENV=development # comment FEATURE_FLAG=true
FAQ
Are my secrets sent somewhere? No. Lint runs entirely in the browser. Prefer not pasting production secrets into any tool.
Is export allowed? Flagged as info/warn — some shells need it; many Node dotenv loaders strip it.
Duplicate keys? Reported as errors; last value usually wins at runtime, which is easy to miss.
Multiline values? Not fully supported. Keep values on one line or use your runtime’s documented escaping.
Does this load env into the page? No. Parse-only report.