HTP Open Platform

Accept USDT payments from millions of HTP users

Add Sign in with HTP and in-app USDT checkout to your website or app. Create a payment on your server, the user confirms it in the HTP App, and you get a signed callback.

Get started API reference

One signed request to get paid

const payment = await htp('POST', '/open/v1/payments', {
  out_order_no: 'A20261107-0001',
  amount: '40.00',
  currency: 'USDT',
  description: 'Premium membership',
  payer_sub: user.htpSub,
}, idempotencyKey);

// Show payment.checkout_url to the user
// → they confirm in the HTP App
// → you receive a signed "payment.paid" callback

What you can build

Sign in with HTP

Standard OpenID Connect with PKCE. Get a stable user ID (sub) to charge and pay users.

Online payments

Create a payment, send users to the HTP cashier, and receive payment.paid when they confirm with their PIN.

Refunds

Refund all or part of a payment instantly from your developer wallet.

Payouts

Send USDT rewards, winnings or settlements to HTP users with one call.

How a payment works

Go live in five steps

1
Register as a developer
Sign in to the console with your verified HTP account and create an app.
2
Apply for payments
Tell us about your business. We approve limits and fees.
3
Get sandbox keys
Create an ok_test_ API key and set your callback URL.
4
Integrate & test
Sign requests, create payments, verify callbacks with test users.
5
Go live
Publish your app, switch to an ok_live_ key, reconcile daily.

Developer tools

Signature generator

Build string_to_sign and X-Signature for any request, and copy a ready curl command.

Callback verifier

Paste a callback you received and check its signature and timestamp.

OpenAPI spec

Download the OpenAPI 3.1 file. Import it into Postman, Insomnia or a code generator.

Ready to integrate?

Open the developer console to create your app and sandbox API keys.