How to Hide API Keys in Frontend Apps (Without a Backend)

If your API key touches the browser, it’s already public. The correct architecture keeps secrets server-side and lets your frontend call a secure endpoint with CORS, rate limits, and server-side header injection.

Create Secure Endpoint View Integrations
  • No Backend Required
  • Server-Side Header Injection
  • CORS Enforcement
  • IP Rate Limiting
  • Abuse Protection

Secure API Key Frontend Architecture Diagram

How to hide API key in frontend secure architecture diagram showing frontend to secure edge bridge to provider API
Frontend → Secure Edge Bridge → Provider API

Why Frontend API Keys Are Always Public

  • Browser DevTools expose headers and network calls.
  • Bundled environment variables are visible at runtime.
  • Anyone can copy your key from the client bundle.
  • Bots automatically scrape exposed API keys.

The Secure Bridge Pattern

Instead of calling providers directly from the frontend, the application calls a secure edge endpoint.

The bridge injects secret headers server-side and forwards validated requests.

CORS policies, rate limits, and abuse controls are applied centrally.

Secure Popular APIs

StripeCreate PaymentIntents securely without exposing your secret key.OpenAICall AI APIs without leaking your OpenAI key.TwilioSend OTP verification securely.SupabaseExecute privileged database operations safely.

Secure Frontend Request Example

javascript
const response = await fetch('https://api.salting.io/r/BRIDGE_UUID', {
  method: 'POST',
  headers: { 'Content-Type': 'application/json' },
  body: JSON.stringify({ action: 'example' })
});

const data = await response.json();

Frequently Asked Questions

Stop Exposing API Keys

Secure your frontend API calls in minutes — without running your own backend.

Create Secure Endpoint