Checkout price is submitted from a hidden form field

Why it matters

A checkout form on this page carries the price in a hidden field named `amount` and submits it to on your site. A hidden field is not protected — it is simply not drawn on screen, and any visitor can change its value from the browser's developer tools before submitting. This lets a visitor set the price they pay. The durable fix is the same either way: send an identifier for what is being bought (a product or price ID) and let the server look up the amount.

How ShipReady detects it

Payment configuration that stops money arriving. The failure this pillar exists for is mundane and catastrophic: a live site wired to a payment provider's TEST environment. Checkout appears to work, the form submits, a success page renders — and no money ever moves. It survives launch because the developer's own testing passes perfectly, and it is usually found when a founder wonders why a week of signups produced no revenue. Deliberately narrow. Every rule here keys off a marker that is definitionally a test credential — Razorpay's `rzp_test_` prefix, Paddle's sandbox environment call, Adyen's test Checkout host. None of them require interpretation, none of them can appear in a correctly configured production deployment, and none of them involve touching the payment provider or attempting a transaction. One marker is shared rather than definitional: `pk_test_` is issued by BOTH Stripe and Paystack. It still proves test mode, so it is still reported — but the provider is resolved from what the page actually loads rather than assumed from the prefix (see _publishable_key_provider). NOT checked, deliberately: whether a checkout page exists or is reachable. Payment routes have no convention — /checkout, /pricing, /billing, /upgrade, /subscribe are all common and most sites have none of them. Probing a list of guesses and reporting the 404s would produce noise on nearly every scan, which is the opposite of what this pillar is for.

Detection is deterministic. ShipReady reports this only when it observes the condition directly, and prefers to miss a real problem over inventing one. Rule version 1.4.0.

How to fix it

This is the prompt ShipReady puts in your report — written to be pasted straight into Cursor, Claude Code, or whichever assistant built the app.

Your checkout form submits the price in a hidden field named amount. Hidden only means not drawn on screen — any visitor can edit it in devtools before submitting, so if your server charges the amount it receives, people can buy at any price they choose. Fix it at the server: stop accepting an amount from the client entirely. Post an identifier for what is being bought (a product ID, or a Stripe/Paddle/Polar price ID) and have the server look up the real amount from your database or the provider's catalogue when it creates the charge — with Stripe, pass `line_items: [{{ price: 'price_xxx', quantity: n }}]` to checkout.sessions.create rather than `unit_amount` computed in the browser. Then verify by intercepting the request, halving the value, and confirming the order is rejected or charged the correct amount. If the form posts straight to a payment provider rather than your own server, no validation is possible at all — switch to a provider-hosted checkout session created server-side.

Frequently asked questions

What does "Checkout price is submitted from a hidden form field" mean?

A checkout form on this page carries the price in a hidden field named `amount` and submits it to on your site.

How serious is it?

ShipReady rates this medium. Fix soon. Meaningfully weakens a defence or degrades how the site works.

How do I fix it?

Paste the fix prompt on this page into Cursor, Claude Code or your AI editor. It is the same prompt ShipReady puts in your report.

Can I check my own site?

Yes — ShipReady scans up to ten pages of any public site for free and reports this alongside every other check. The free report lists every issue it finds and shows full evidence and a fix prompt for the critical and high-severity ones; medium and low findings are counted and unlock on Pro.

Related checks

• A payment form submits over an unencrypted http:// connectionhigh
• Card details are collected by your own page, not a hosted payment fieldhigh
• Payment test mode keyhigh
• Working discount codes are compiled into the browser bundlehigh
• A PayPal order is priced in the browsermedium
• Both live and test Stripe keys are shipped to the browsermedium