How to Price x402 API Calls in USDC for 2026

Sellers setting x402 API prices in USDC must publish an accepts entry that names the payment scheme, the USDC amount, the CAIP-2 network and a payTo address. Coinbase’s CDP Facilitator provides the verification and settlement path; the first 1,000 on-chain settlements per month are free, and each additional on-chain transaction costs $0.001.

On x402 the price field is a payment instruction sent with HTTP 402 Payment Required. The accepts entry must list the scheme, the price in USDC formatted for the SDK, the CAIP-2 network identifier and an on-chain payTo address controlled by the seller. After a buyer pays the instruction, a CDP Facilitator verifies and settles the transfer; only then should the seller return the requested resource.

Coinbase’s CDP documentation lists three settlement schemes for EVM networks — exact, upto and batch-settlement — and exact only for Solana. Exact and upto each produce one on-chain settle per accepted payment. Batch-settlement verifies vouchers off-chain and can cover many accepted payments with a single on-chain claim, spreading the $0.001 fee across multiple tickets.

A ticket priced at $0.001 settled under exact or upto will be fully consumed by the Facilitator fee once the free tier is exceeded, before accounting for gas, infrastructure or compute costs. For high volumes of sub-cent calls, sellers should use batch-settlement on a supported EVM chain so the $0.001 cost divides across many payments. Solana supports exact only in the CDP table; for batch economics sellers should use an EVM network such as Base.

Traffic and volume figures underline the scale of the rail. x402.org recorded about 75.41 million transactions and $24.24 million in volume in the 30 days ending Aug. 24, 2026, with typical tickets under $0.50. Coinbase’s Developer Platform reports its Facilitator has processed more than 100 million transactions and roughly $28 million in volume across Base and Solana.

Sellers should lock the four accepts fields to treasury policy before shipping middleware: choose the scheme that matches the product (exact for fixed-price SKUs, upto for metered calls with a hard cap, batch-settlement for high-frequency sub-cent traffic), set the price as a USDC string the SDK accepts (for example “$0.01”), set the network (prefer Base mainnet CAIP-2 eip155:8453) and set payTo to an address the seller controls on that network. Circle’s native Base USDC mainnet address to advertise is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913. Do not mix Solana payees with EVM accepts.

Sellers must perform floor math before publishing accepts: estimate paid calls per month above the first 1,000 free settlements, multiply excess settles by $0.001 for exact and upto, or divide $0.001 by payments per claim for batch-settlement. Require each ticket to be at least N times that unit cost, where N is a written margin multiple. Deposits, refunds and withdrawals each count as separate on-chain transactions in CDP’s model and should be included in the budget.

Testing and cutover steps start on Base Sepolia (CAIP-2 eip155:84532) using a test facilitator path and a small exact price. When ready for production, flip both the facilitator URL and the CAIP-2 network to the CDP production endpoint (https://api.cdp.coinbase.com/platform/v2/x402 and Base mainnet) and confirm the first live settlement hash, token contract, amount and payTo before recognizing revenue. Implement know-your-agent checks and buyer-side spend limits so repeat payers or anonymous agents cannot trigger costly settlements without caps.