Lovable Stripe Checkout Fails or Cards Are Declined
Quick Answer
How do I fix Lovable Stripe Checkout Fails or Cards Are Declined?
Using live Stripe keys instead of test keys, or missing STRIPE_WEBHOOK_SECRET in Vercel environment variables. Start with "Verify test mode" before making broader code changes.
Fix signals
- What this answers
- Why lovable stripe checkout fails or cards are declined happens and what to change first.
- Fastest move
- Verify test mode
- Use this page if
- Payment form shows but card is declined
If this keeps happening
Open the next decision, not just the patch
Use these when the current fix is helpful, but the real answer is a better tool choice, a cleaner workflow layer, or a more trustworthy launch path.
Lovable reviews
Open this when the same full-stack MVP failures keep repeating and you need a harder answer on whether Lovable is still the right bet.
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Cursor review
Open this when the pattern behind the bug is really about generated speed versus owning more of the stack in code.
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Deploy hub
Open this when the fix is exposing a bigger production handoff problem, not just one broken feature.
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Tool picker
Open this when the repeated bug is making you question the whole stack choice instead of the latest patch.
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Firecrawl review
Open this when the app also needs live web data and the next stack decision is no longer only about the builder itself.
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Quick Fix Summary
| Most likely cause | Using live Stripe keys instead of test keys, or missing STRIPE_WEBHOOK_SECRET in Vercel environment variables. |
| Fastest fix | Verify test mode |
| Use this page if | Payment form shows but card is declined |
Exact errors people search for
If one of these matches what you are seeing, you are likely on the right fix page.
Payment form shows but the card is declined Stripe checkout redirects to an error page Stripe dashboard shows no test payments after checkout
You're in the right place if...
- !Payment form shows but card is declined
- !Checkout redirects to error page
- !Stripe dashboard shows no test payments
Why this happens
Using live Stripe keys instead of test keys, or missing STRIPE_WEBHOOK_SECRET in Vercel environment variables.
Fix
Verify test mode
Stripe Dashboard → toggle 'Test mode' on (top right) → Developers → API keys. Keys should start with pk_test_ and sk_test_. If they start with pk_live_, you're in live mode.
Add all Stripe vars to Vercel
Go to Vercel → Settings → Environment Variables and add:
NEXT_PUBLIC_STRIPE_PUBLISHABLE_KEY=pk_test_... STRIPE_SECRET_KEY=sk_test_... STRIPE_WEBHOOK_SECRET=whsec_...
Test with Stripe's test card
Use this card number for testing:
Card: 4242 4242 4242 4242 Expiry: any future date (e.g. 12/34) CVC: any 3 digits (e.g. 123)
Prevent this next time
Always start with test keys (pk_test_, sk_test_). Only switch to live keys after everything works perfectly in test mode.
Frequently Asked Questions
Test keys start with pk_test_ and sk_test_. Live keys start with pk_live_ and sk_live_. Check in Stripe Dashboard → Developers.
Stripe Dashboard → Developers → Webhooks → your endpoint → Signing secret. Starts with whsec_.
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