Check and decode crypto addresses, hashes, selectors and units without a node.
payments ON MAINNET (real money) · 12 live endpoints
| Endpoint | Price | What it answers |
|---|---|---|
GET /btc-address | $0.02 | Validate a Bitcoin address (legacy, P2SH, SegWit bech32, Taproot bech32m): checksum, type, network and hash payload. |
GET /caip-parse | $0.02 | Parse CAIP-2 chain ids, CAIP-10 account ids and CAIP-19 asset ids: namespace, reference, known chain name, address check. |
GET /calldata-split | $0.02 | Split EVM calldata into its 4-byte selector and 32-byte words, naming common ERC-20/721 calls and spotting addresses. |
GET /contract-address | $0.02 | Predict a contract address: CREATE from deployer and nonce, or CREATE2 from deployer, salt and init code (or its hash). |
GET /ens-namehash | $0.02 | Compute the ENS namehash (EIP-137) and label hashes for a name such as vitalik.eth, for contract calls and subgraph queries. |
GET /evm-address | $0.02 | Check an EVM address (Ethereum, Base, Polygon...) against its EIP-55 checksum and return the correctly checksummed form. |
GET /function-selector | $0.02 | Compute the 4-byte function selector and event topic0 from a Solidity signature such as transfer(address,uint256). |
GET /hex-convert | $0.02 | Convert hex to UTF-8 text or an integer (signed or unsigned), and text or integers to hex with 32-byte padding. |
GET /keccak256 | $0.02 | Keccak-256 hash (the Ethereum one) of text or hex bytes, with the first-4-byte selector and NIST SHA3-256 for contrast. |
GET /solana-address | $0.02 | Validate a Solana address: base58, 32 bytes, and whether it is on the ed25519 curve (wallet) or off it (program-derived). |
GET /tx-hash-check | $0.02 | Recognise what a transaction id looks like (EVM hash, Bitcoin txid, Solana signature) from format alone, and flag typos. |
GET /unit-convert | $0.02 | Exact unit conversion for crypto amounts: wei, gwei, ether, lamports, SOL, satoshis, BTC or a token with N decimals. |
GET /catalog returns this list as JSON. Activity hub · uptime.
Computed locally from public specifications. A well-formed address or valid checksum does not mean the address exists, is funded, or belongs to anyone; nothing here sends a transaction, holds keys or gives financial advice. Every paid response carries a disclaimer field.