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Wire up your first payment

Our most-read guide walks you through your first card charge using the Payment Element, end to end.

Pick the Flip server SDK that fits your stack — Node, Python, Ruby, PHP, Go, Java, or .NET — and pull it in. Stash your secret key in a server-side environment variable so it never leaves the backend. Most teams keep a separate test key for local work and a production key behind their secrets manager.

On the server side, create a PaymentIntent for every checkout attempt. The PaymentIntent is the durable object that tracks a payment through its full lifecycle: creation, authorization, capture, refund, or failure. Provide the amount in the smallest currency unit alongside the currency code — Flip will fill in sensible defaults for the rest.

On the client, mount the Payment Element using the client secret that came back from your server. The Element renders a payment form that adapts to the customer's region and the methods you've enabled — cards, wallets, ACH, BNPL, stablecoins, and bank redirects all surface without extra code.

When the customer hits submit, fire flip.confirmPayment with a return URL. Flip walks them through any 3DS or redirect step required, then routes them back. On the server, subscribe to webhooks to update orders, kick off fulfillment, or trigger provisioning — webhooks are the source of truth for what actually happened.

curl https://api.flip.com/v1/payment_intents \
  -u sk_test_xxx: \
  -d "amount=2000" \
  -d "currency=usd" \
  -d "automatic_payment_methods[enabled]=true" \
  -d "description=Order #1234" \
  -d "metadata[customer_id]=cus_AbCdEf"

Send an Idempotency-Key header on writes so retries during network blips don't produce duplicate charges.

Read the full guide →