Pay-per-call APIs
Endpoints an agent can buy one request at a time (Lightning L402, x402 USDC, MPP), sorted by price per call. Prices are read from the HTTP 402 challenge each endpoint returned to an unpaid request (nothing was paid). Sat prices use an approximate USD rate only for sorting and display.
endpoints that answered HTTP 402
418
one unpaid request each, nothing was paid
cheapest call
$0.0001
Object Storage: List objects
last probed
2026-10-18
prices are re-read from the live 402 challenge
Plain-English meanings
- HTTP 402
- “Payment Required”: a web status code a server sends when a request has to be paid for first.
- 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.
- x402
- The same pay-first idea for APIs, but paid in USDC (a dollar stablecoin) instead of Bitcoin.
- MPP
- Machine Payments Protocol: an open standard that lets agents pay for web services per request, with stablecoins or other payment methods.
- USDC
- A digital dollar: a crypto token meant to always be worth one US dollar.
- sats
- A satoshi (sat) is one hundred-millionth of a bitcoin.
01
$0.0001USDC.e (MPP)
endpoint (not a link, to avoid accidental calls):
https://storage.mpp.tempo.xyz/price basis: amount in the unpaid HTTP 402 Payment (MPP) challenge, USDC.e 6 decimals
“HTTP 402 + MPP Payment challenge (method=tempo): amount 100 atomic units of USDC.e (= $0.0001)”
source: storage.mpp.tempo.xyz/
last checked 2026-10-17
02
$0.0001USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://x402-wrapper.onrender.com/v1/echoprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 100 atomic units of USD Coin (= $0.0001)”
last checked 2026-10-17
03
1 sat≈ $0.0008
endpoint (not a link, to avoid accidental calls):
https://api.loopxxi.com/v1/chat/completionsprice basis: invoice amount decoded from an unpaid HTTP 402 response
“HTTP 402 + L402 invoice for 1 sat(s)”
last checked 2026-10-17
402 Index listed price: 1 sat (the probe value above is what is shown)
04
1 sat≈ $0.0008
endpoint (not a link, to avoid accidental calls):
https://raikiri.org/v1/helloprice basis: invoice amount decoded from an unpaid HTTP 402 response
402 Index listed price: 1 sat (the probe value above is what is shown)
05
1 sat≈ $0.0008
endpoint (not a link, to avoid accidental calls):
https://parsebit-lnd.fly.dev/analyse/compareprice basis: invoice amount decoded from an unpaid HTTP 402 response
“HTTP 402 + L402 invoice for 1 sat(s)”
last checked 2026-10-17
402 Index listed price: 1 sat (the probe value above is what is shown)
06
$0.0010USDC.e (MPP)
endpoint (not a link, to avoid accidental calls):
https://api.aisa.one/apis/v1/airbnb/searchprice basis: amount in the unpaid HTTP 402 Payment (MPP) challenge, USDC.e 6 decimals
“HTTP 402 + MPP Payment challenge (method=tempo): amount 1000 atomic units of USDC.e (= $0.001)”
last checked 2026-10-17
07
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://apiacre.com/v1/crypto/base-block-inspectprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
last checked 2026-10-18
08
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://agent402.tools/api/hashprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
source: agent402.tools/api/hash
last checked 2026-10-18
09
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://x402.agentindex.world/can-payprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
source: x402.agentindex.world/can-pay
last checked 2026-10-17
10
$0.0010USDC.e (MPP)
endpoint (not a link, to avoid accidental calls):
https://mpp.alchemy.com/:network/nft/v3/:endpointprice basis: amount in the unpaid HTTP 402 Payment (MPP) challenge, USDC.e 6 decimals
“HTTP 402 + MPP Payment challenge (method=tempo): amount 1000 atomic units of USDC.e (= $0.001)”
last checked 2026-10-17
11
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://x402.rpc.ankr.com/monad_mainnetprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USDC (= $0.001)”
source: x402.rpc.ankr.com/monad_mainnet
last checked 2026-10-18
12
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://base-onchain-tools.dolerite.workers.dev/v1/base/allowanceprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
last checked 2026-10-18
13
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://market.561.group/v1/base-chain/gas-oracleprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
last checked 2026-10-17
14
Brand Extractor — logos, colors and fonts (alias)x402stablecoin402 seen 2026-10-17design/brand-extraction
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://extract.ilyyya.com/api/v1/extract-logo-colors-fontsprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
last checked 2026-10-17
15
Brand Extractor — website logos, colors & fontsx402stablecoin402 seen 2026-10-17design/brand-extraction
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://extract.ilyyya.com/api/v1/extract-brandprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
last checked 2026-10-17
16
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://twitter.surf.cascade.fyi/trendsprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
source: twitter.surf.cascade.fyi/trends
last checked 2026-10-17
17
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://api.clawfetch.ai/fetchprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
source: api.clawfetch.ai/fetch
last checked 2026-10-17
18
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://api.crinkl.xyz/x402/crinkl-verified-commerce-signalsprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
last checked 2026-10-18
19
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://rooms.aurmada.com/x402/v1/email/checkprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
last checked 2026-10-17
20
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://moneytest-x402-api.indierepo.chatgpt.site/v1/x402/canonical-receiptprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
last checked 2026-10-17
21
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://x402-trading.useotto.xyz/hyperliquid-accountprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
last checked 2026-10-17
22
Pinata IPFS: Upload file to IPFS — dynamic pricing based on file size ($0.10/GB/month, minmppstablecoin402 seen 2026-10-17storage
$0.0010USDC.e (MPP)
endpoint (not a link, to avoid accidental calls):
https://mpp.pinata.cloud/v1/pin/publicprice basis: amount in the unpaid HTTP 402 Payment (MPP) challenge, USDC.e 6 decimals
“HTTP 402 + MPP Payment challenge (method=tempo): amount 1000 atomic units of USDC.e (= $0.001)”
source: mpp.pinata.cloud/v1/pin/public
last checked 2026-10-17
23
SettlementWitness — Verifiable Agent Settlement Layer (Solana)x402stablecoin402 seen 2026-10-17commerce/settlement
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://defaultverifier.com/x402/settlement-witness-solanaprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
last checked 2026-10-17
24
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://api.sitecheck-api.workers.dev/api/crypto/price?symbols=BTC,ETHprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
last checked 2026-10-18
25
$0.0010USDC (x402)
endpoint (not a link, to avoid accidental calls):
https://stableemail.dev/api/inbox/messagesprice basis: USDC amount in the unpaid HTTP 402 payment challenge (first accepted option)
“HTTP 402 + x402 v2 challenge: amount 1000 atomic units of USD Coin (= $0.001)”
last checked 2026-10-18
showing 25 of 418 matches
USD rate used: $0.00081513 per sat (ratio of price_usd/price_sats in 402 Index API responses on 2026-10-15 (approximate, used only for sorting)).