Sandbox vs live mode

Every SellStein account starts in sandbox. Real money flips on after underwriting. Here's how to use the sandbox without breaking anything.

What runs in sandbox

Everything visible in the dashboard runs the same. Products, customers, orders, refunds, webhooks. Payments hit a test processor that returns synthetic responses (auth, decline, 3DS challenge, etc.) based on the card number you use.

Test cards

The big four:

• 4111 1111 1111 1111. Visa, always succeeds
• 4000 0000 0000 0002. Visa, always declines (processor error)
• 4000 0027 6000 3184. Visa, always triggers 3DS challenge
• 4242 4242 4242 4242. Stripe-flavoured default success card

Use any future expiry date and any 3-digit CVC. Real card numbers in sandbox are rejected.

What's mocked

Settlement, payouts, dispute lifecycle, and tax-authority calls are all mocked in sandbox. You won't see real bank transfers; the Payouts page shows synthetic payouts on the same schedule the live mode would.

Webhook signatures are real even in sandbox. Verify yours work before going live.

What is NOT mocked

Email sends. SMS sends. Anything you trigger from the dashboard that goes to a third-party endpoint will actually reach that endpoint. Don't connect your real Klaviyo or Twilio account to sandbox. Use a separate sandbox account on those platforms too, or you'll spam your real users.

Going live

When KYC is approved (1-5 business days), the dashboard shows a "Go live" banner. One click flips your store. After that:

• Sandbox data stays. Products, customers, orders all carry over to live
• Test transactions are gone (we delete them on the flip; they were synthetic)
• Webhooks point at the live endpoint URLs you set in Settings → Developers → Webhooks
• API keys: live keys start with sk_live_ instead of sk_test_

Going back

You can switch a live store back to sandbox for testing. Top right of the dashboard, mode toggle. Customers and orders are split per-mode so live data is never touched. Useful for testing risky integrations on a real-data clone.

What to do first in sandbox

Place a test order, refund it, dispute it (use card 4000 0000 0000 0259 to auto-trigger a chargeback), and trigger a webhook. If those four work end to end, your integration is solid.