Blockchain And Crypto x402 offerings

Latest block number on Base, Ethereum, Arbitrum, Optimism, Polygon or BSC. $0.01 per call.

Is this address a contract? Bytecode size, EIP-1967 proxy implementation and EIP-7702 delegation. Default chain Base; prefix another: ethereum:, arbitrum:, optimism:, polygon:, bsc:. $0.01 per call.

ERC-20 allowance a wallet has granted a spender, and whether it is unlimited: send "token,owner,spender". Default chain Base; prefix another: ethereum:, arbitrum:, optimism:, polygon:, bsc:. $0.01 per call.

ERC-20 token balance of a wallet, read live on-chain: send "token,wallet". Default chain Base; prefix another: ethereum:, arbitrum:, optimism:, polygon:, bsc:. $0.01 per call.

Current gas price, base fee and priority fee in gwei plus the cost of a plain transfer, for Base, Ethereum, Arbitrum, Optimism, Polygon or BSC. $0.01 per call.

Native coin balance (ETH/POL/BNB) of any address, read live from the chain. Default chain Base; prefix another: ethereum:, arbitrum:, optimism:, polygon:, bsc:. $0.01 per call.

Live total supply of an ERC-20 token, decimals applied. Default chain Base; prefix another: ethereum:, arbitrum:, optimism:, polygon:, bsc:. $0.01 per call.

CREATE2 deterministic contract address calculator — derive the EIP-1014 EVM deployment address, preimage, hashes, and EIP-55 checksum offline without RPC.

EVM address checksum and validation tool — normalize one Ethereum-compatible address and validate mixed-case EIP-55 input offline.

Strict Solidity ABI calldata decoder — decode canonical EVM smart-contract function calls or typed values, verify selectors, and reject ambiguous offsets or padding.

Solana Program Derived Address (PDA) calculator — derive the canonical off-curve address and bump from bounded public seeds offline, without RPC or key handling.

Solidity ABI calldata encoder — encode canonical typed values for an EVM smart-contract function call, with an optional selector and exact 256-bit integers.

Raw transaction by hash: from, to, value, nonce, block, gas, type, method selector, pending flag. Default chain Base; prefix another: ethereum:, arbitrum:, optimism:, polygon:, bsc:. $0.01 per call.

Transaction receipt: success or failed, gas used, fee paid, logs, token-transfer events, created contract. Default chain Base; prefix another: ethereum:, arbitrum:, optimism:, polygon:, bsc:. $0.01 per call.

Live ERC-20 spending allowance an owner has granted a spender: calls `allowance(owner, spender)` on the token and returns the raw amount, a decimal-formatted amount (using the token's decimals) with …

Resolve an ENS name (like alice.eth) to its Ethereum address, read live from the ENS resolver on Ethereum mainnet. Offchain names such as *.base.eth resolve too. Returns `found:false` (a real answer,…

Live gas conditions for an EVM chain: current gas price, the latest block's base fee (EIP-1559) and the suggested max priority fee — all in both wei and gwei. Ground truth an agent can't compute. Rea…

Live snapshot of the Bitcoin mempool: number of unconfirmed transactions, total pending virtual size (bytes and MB), the current backlog in blocks, total fees pending (sats and BTC), the fee-rate his…

Live recommended Bitcoin transaction fee rates (in sat/vB) for next-block, ~30-minute, ~1-hour, economy and minimum confirmation targets, straight from the mempool. Also estimates the total fee (in s…

Look up a Bitcoin transaction by txid: confirmation status, block height and time, fee (sats), effective fee rate (sat/vB), size, weight and virtual size, input and output counts, and total output va…

Read an ENS name's address plus its text records (avatar, url, email, description, com.twitter, com.github and more) in one call, live from the resolver on Ethereum mainnet. Pass `keys` to fetch spec…

Fetch deployed EVM contract runtime bytecode and its Keccak-256 code hash to fingerprint or compare contracts, or feed a disassembler. Supports Ethereum, Base, Arbitrum, Optimism and Polygon, with op…

Simulate a transaction before signing: runs `eth_estimateGas` for `{ to, from?, data?, value? }` and returns the estimated gas units and estimated fee (current gas price x gas, in wei + ETH). If the …

Detect whether a contract is an upgradeable proxy and resolve its implementation: reads the standard EIP-1967 implementation/admin/beacon slots, EIP-1822 (UUPS), the OpenZeppelin legacy slot, and EIP…