Blockchain Lab Tools

Build a Safe transaction and compute its EIP-712 safeTxHash locally, cross-check against the Safe contract on-chain, read owners/threshold/nonce, and decode execTransaction or MultiSend batches.

Hash EIP-712 typed data (digest, domain separator, struct hash), sign with a throwaway key or your wallet, recover the signer, verify personal_sign messages and check ERC-1271 smart-account signatures on-chain.

Decode two calldata blobs (or two tx hashes) with openchain/4byte signatures and highlight every argument and 32-byte word that differs.

Check whether a smart contract's source code is verified on Sourcify (full/partial match) and Blockscout, with compiler version, licence, proxy type and implementation addresses.

Chart base fee, median priority tip and block fullness over the last 1,024 blocks for Ethereum, Base, Arbitrum, OP, Polygon, BNB Chain and Avalanche, with min/median/p75/max stats.

Compare live quotes for bridging USDC or ETH between Ethereum, Base, Arbitrum, OP and Polygon: amount received, fees and estimated time from Across, LI.FI and Relay.

Check which popular spenders (Permit2, Uniswap, 1inch, 0x, CoW, Balancer, OpenSea, Aave…) can move an address's ERC-20 tokens, flag unlimited approvals, and get one-click revoke links and approve(spender, 0) calldata.

Resolve a list of ENS names to addresses (with avatar, url, Twitter, GitHub records) and reverse-resolve addresses to primary names, verifying forward/reverse match. Export as CSV.

Decode any Solana transaction signature: status, fee, compute units, parsed instructions and inner instructions with program names (Jupiter, Raydium, Orca, Meteora, SPL Token…), SOL and token balance changes, and logs.

Decode a Bitcoin PSBT (BIP-174, base64 or hex) or raw transaction: inputs, outputs, addresses, script types, fee and fee rate, signatures present, BIP-32 derivation paths. Runs offline in your browser.

Look up public labels for an EVM address: Blockscout contract name and public tags, token info, ENS primary name, Uniswap token-list match, well-known spender names, and an OFAC SDN sanctions check.

Estimate how many attempts and how long it takes to find an Ethereum vanity address prefix (case-insensitive or EIP-55 checksum), benchmarked live on your device, and compute CREATE2 deployment addresses.

Quote a Uniswap v3 swap on-chain with QuoterV2 and see amount out, mid price, execution price, price impact, price after the trade, ticks crossed and gas estimate — Ethereum, Base, Arbitrum, OP, Polygon.

Paste an Ethereum/Base/Arbitrum/OP/Polygon transaction hash to check whether it was sandwiched: finds a front-run swap on the same pool in the same direction and a back-run reversing it from the same EOA or bot contract.

Live stablecoin table: price vs peg, circulating supply, 7-day supply change, peg mechanism and chain count for 400+ stablecoins from DefiLlama.

Test free public RPC endpoints for Ethereum, Base, Arbitrum, OP, Polygon, BNB Chain and Avalanche from your browser: reachability, latency, chain ID and how many blocks behind the best endpoint each is. Plus the nightly server-side probe.

Live gas prices and transaction cost in USD across EVM chains, Bitcoin sat/vB and Solana priority fees, read directly from public RPCs.

Exact big-number conversion between wei, gwei, ether, satoshis, BTC, lamports and SOL — no floating point errors.

Encode Solidity function calls, decode calldata, compute 4-byte selectors and event topics, and look up unknown selectors in the openchain / 4byte signature databases.

Validate EIP-55 checksums, resolve ENS names (forward and reverse), and inspect any address on Ethereum, Base, Arbitrum, OP, Polygon, BNB or Avalanche: balance, nonce, contract code, proxy implementation, EIP-7702 delegation and ERC-20 metadata.

Paste a transaction hash to decode the function call, arguments, event logs, status and fees on Ethereum, Base, Arbitrum, Polygon, OP Mainnet, BNB Chain and Avalanche via public RPC.

Hash text or hex with keccak256, sha256 and ripemd160, and build OpenZeppelin-compatible Merkle trees (StandardMerkleTree / SimpleMerkleTree) with root and proofs for airdrops and allowlists.

Compute Solidity storage slots for mappings, nested mappings, dynamic arrays, ERC-7201 namespaces and EIP-1967 proxy slots — then read the live value from any EVM chain.

Search every Ethereum EIP and ERC and every Bitcoin BIP by number, title or status. Rebuilt nightly from ethereum/EIPs, ethereum/ERCs and bitcoin/bips.

Search 2,700+ EVM networks by name or chain ID, test public RPC latency live from your browser, and add a network to MetaMask/any EIP-3085 wallet.

Search the Uniswap default token list by symbol, name or address across Ethereum, Base, Arbitrum, OP, Polygon, BNB and Avalanche, and verify any token's on-chain name, symbol, decimals and supply.