x402 vs L402: how AI agents pay per API call
x402. The same pay-first idea for APIs, but paid in USDC (a dollar stablecoin) instead of Bitcoin.
L402. A way for an API to say “pay first”: it replies with a Lightning invoice, the agent pays a few sats, then gets its answer.
Side by side
| From our data | x402 | L402 |
|---|---|---|
| APIs listed | 367 | 132 |
| Paid in | USDC (Base) (357 of 367) | BTC (Lightning) (132 of 132) |
| Cheapest per call | $0.0001 · x402wrapper | $0.0008 (1 sat) · Loop Gateway (and 3 more at the same price) |
| Median price per call | $0.010 | $0.0082 |
| Payment services at YES with this rail | 331 (rail x402) | 11 (rail l402) |
| Wallets supporting it | 54 (rail x402) | 123 (rail lightning, since L402 runs on Lightning; 3 also list the l402 rail itself) |
Prices are read from the unpaid HTTP 402 challenge each API returned. Nothing was paid. Sat prices use $0.00081513 per sat for the dollar figure.
Cheapest 5 x402 APIs
- x402wrapper · $0.0001 (USDC (x402)) · x402-wrapper.onrender.com
- API Acre — Base block inspection · $0.0010 (USDC (x402)) · API Acre
- Agent402 hash (MPP) (x402) · $0.0010 (USDC (x402)) · Havok Holdings LLC
- Agent402 stock-quote (MPP) (x402) · $0.0010 (USDC (x402)) · Havok Holdings LLC
- AgentIndex can-pay (MPP) · $0.0010 (USDC (x402)) · AgentIndex
Cheapest 5 L402 APIs
- Loop Gateway · 1 sat (≈ $0.0008) · Loop XXI LLC
- Raikiri: your first L402 purchase (1 sat test endpoint) · 1 sat (≈ $0.0008) · Raikiri
- parsebit-lnd.fly.dev: Code explanation endpoint that accepts code or a code-file URL and r · 1 sat (≈ $0.0008) · parsebit-lnd.fly.dev
- parsebit-lnd.fly.dev: L402 · 1 sat (≈ $0.0008) · parsebit-lnd.fly.dev
- Air Quality Index: Current · 2 sat (≈ $0.0016) · Lightning Enable
Data as of 2026-10-24. How we check: /method.