What is Numpay?
Numpay is a mobile-first payments app for sending and requesting crypto using a mobile number or an email address. It feels like a normal payments app: you sign in with a one-time code, see your balance, and send money to a contact. Behind the scenes every payment settles on a blockchain, and balances are shown in dollars because the crypto Numpay uses is pegged 1:1 to the US dollar.- No bank account, seed phrase or wallet app needed. You sign in with a code sent to your mobile number or email.
- No gas fees for users. Numpay pays the network fee for every transfer.
- Pay people who haven’t joined yet. Their money waits safely and moves to them automatically when they first sign in.
- Request money with a link. Ask a specific person, or share a link anyone can pay.
How it works
The whole system explained in plain language, with simple diagrams.
Key concepts
Crypto, smart wallets, sponsored gas and claimable wallets in one page.
Architecture
The full technical picture: components, flows and data model.
API reference
Every endpoint of the Numpay backend, with request and response shapes.
Numpay at a glance
Who this documentation is for
- Users and partners
- Engineers
Start with How it works and the Using Numpay guides. They explain what happens when you sign in, send, request and add money, without any code.