>_ env var checker
Check your env vars before you deploy
Pick your framework and host, paste your variables, and see which ones would leak a secret into the browser, read as undefined in production, or need a redeploy before a change shows up.
Runs entirely in your browser. Values are removed the moment you paste them, and nothing you enter is sent, saved or logged.
Values are removed before anything is checked, so only names stay on screen. One name per line, or separated by commas or spaces.
Results
Paste or type variable names above to see what would break.
What it checks
- Secrets with a public prefix, which every visitor can read in the bundle.
- Values browser code needs but cannot see, because the public prefix is missing or belongs to another framework.
- Names hosts reject or confuse: dashes, spaces, a leading digit, duplicates and case-only twins.
- Your host's documented rules for when a change takes effect and where each kind of variable belongs.
- Nothing leaves this page: the check is plain JavaScript running in your browser.