How to hide API keys in Lovable
Short answer: Keep secret keys in a Supabase Edge Function, using Lovable’s Supabase secrets flow. Lovable frontend code ships to the browser; hiding a value in a component or a frontend environment variable does not keep it private.
Ember can help check what your published app shows a visitor. Run a free SniffPup scan of your own site. Passive checks only; a clean scan is not proof of security.
Home › Guides › Hide API keys in Lovable · Last updated · By Ember, SniffPup
1. Find the browser boundary
Search frontend code and browser Network requests for secret keys and direct provider calls. Public keys such as Supabase’s anon or publishable key are designed for client use, with RLS protecting data. Provider secret keys and service_role keys belong on the server.
2. Move the call to a Supabase Edge Function
Ask Lovable to move the provider request into a Supabase Edge Function and store the key using its Supabase secrets flow. Read it only in the function with Deno.env.get("PROVIDER_API_KEY"). The frontend calls your function and receives only the result, never the key.
3. Check the caller before using the secret
Validate the caller’s session and permission to perform the action. Validate inputs, limit requests, and return only needed data. A hidden key behind an unrestricted endpoint still lets strangers trigger provider calls.
4. Rotate any secret that reached client code
Revoke an exposed secret promptly in the provider dashboard. Create a replacement, save it only as a backend secret, deploy the function and frontend changes, and review provider usage. Removing a key from source does not erase old bundles or copies.
5. Check the published app
Search loaded JavaScript and inspect Network requests on your own live URL. Confirm the browser calls your function without sending the provider key. Test the function signed out and as a user without permission. A clean scan is not proof of security.
Next: Are VITE_ environment variables public?, Audit your Lovable app and Leaked API key: what to do.
FAQ
Does a Lovable .env file hide my key?
Not if frontend code reads the secret into the browser bundle. Use a backend function secret instead.
Should I rotate a key that was in Lovable client code?
Yes. Treat a secret in client code as exposed, revoke it, and use a new server-only key.
Sources: Lovable Supabase integration and Supabase function secrets, checked November 5, 2026.