Firebase Google Login Error: auth/unauthorized-domain – Step-by-Step Fix

✅ How to Fix auth/unauthorized-domain for Google Login in Firebase

🔧 Step-by-Step:

🟢 1. Go to Firebase Console

Visit: https://console.firebase.google.com/

1. Select your project
2. Go to Authentication (from the left sidebar)
3. Click on the "Sign-in method" tab

🟢 2. Enable Google Sign-In (if not already)

• In the Sign-in providers list, click Google
• Make sure it's Enabled
• Set your project’s public-facing name
• Click Save

🟢 3. Add Authorized Domains

Still under Authentication > Sign-in method, scroll to the "Authorized domains" section.

Click "Add domain", and add the domain where your app is running, for example:

admin.ts-geosystems.com.bd

Also add:

localhost

(if you're testing locally)

✅ Make sure it includes the exact domain/subdomain you're using in your frontend (without https:// or slashes).

🟢 4. Save and Retry

After adding the correct domains:

• Clear your browser cache (optional but helps)
• Restart your frontend app
• Try logging in with Google again

🛡️ Optional Security Tip

If you're deploying to multiple environments (dev, staging, production), make sure all domains are whitelisted in Firebase under Authorized domains.