Amex Do Not Honor Test Card Numbers
Amex · Do Not Honor: do_not_honor is a generic issuer decline with no further detail. Many apps map it to a generic card error — test that you do not leak internal codes to end users.
American Express uses 15-digit card numbers and separate CVV rules. MockCard generates Amex-shaped test data so formatting validators pass before you hit a real gateway.
When to use: Regression-test generic decline UX and support tooling that buckets unknown declines.
CI tip: Log decline_code from the webhook payload; MockCard mirrors Stripe-shaped error envelopes.
Typical decline_code in webhook payloads: do_not_honor.
Click card to flip
Same scenario, other networks
Need webhook race conditions or 3DS abandonment? See payment failure testing and the API docs. Compare plans on pricing.
API example
const res = await fetch("https://mockcard.io/api/v1/generate", {
method: "POST",
headers: {
"Content-Type": "application/json",
"X-Api-Key": process.env.MOCKCARD_API_KEY ?? "",
},
body: JSON.stringify({
brand: "visa", // visa | mastercard | rupay | amex
scenario: "success", // success | insufficient_funds | 3ds_challenge …
}),
});
const card = await res.json();
// { card_number, expiry_month, expiry_year, cvv, brand, scenario }
console.log(card.card_number, card.cvv);