Web3
Decode a raw Ethereum transaction or an EIP-7702 delegation, read what a typed-data signature would hand over before you sign it, verify who signed an Ethereum message or a sign-in, compare a Safe transaction’s hashes with your hardware wallet, look for reused ECDSA nonces, inspect PSBTs and xpubs, and verify Bitcoin (BIP-137/322), Solana and Nostr signatures. Everything runs in your browser; on-chain lookups go to a public RPC node only when you ask. Seed phrases and private keys are never accepted.
13 tools
Nonce Reuse Checker
Scan a Bitcoin address for repeated r values
ECDSA's one fatal mistake: signing twice with the same nonce reveals the private key. Paste a Bitcoin address — the checker scans its historical signatures for repeated r values, the fingerprint of nonce reuse.
Open toolEIP-712 Inspector
What a typed-data signature really allows
Paste the typed data a site asks your wallet to sign and read, in plain words, what the signature allows: token permits, Permit2 allowances, Seaport, Blur, LooksRare and CoW orders. Flags unlimited approvals, listings that pay you nothing, far-off deadlines, the wrong chain and look-alike contracts.
Open toolEthereum Signature Verifier
Who signed this Ethereum message?
Recover and verify the signer of an Ethereum signature — personal_sign, EIP-712 typed data or a raw eth_sign hash — with every intermediate hash. When it does not match, it tries the usual mix-ups and says which one happened; smart-contract wallets are checked on chain through ERC-1271 and ERC-6492.
Open toolSIWE Verifier
Check a Sign-In with Ethereum message
Paste a Sign-In with Ethereum message and its signature: the verifier parses it strictly against EIP-4361, pinpoints every malformed line, recovers the signer and runs the checks a relying party must make — domain, request origin, nonce, chain, address, URI and the validity window. Smart wallets are checked on the message’s chain.
Open toolSafe Transaction Hash
Check what your Safe signers really sign
Compute the three hashes a hardware wallet shows when you sign a Safe{Wallet} transaction — domain hash, message hash and safeTxHash — for every Safe version, and compare them with your screen. Decodes owner and module changes, guards and MultiSend batches, flags DELEGATECALL and gas refunds, checks owner signatures, and can have the Safe itself confirm the hash.
Open toolEthereum Transaction Decoder
Decode raw signed transactions
Paste a raw transaction or an eth_getTransactionByHash object: every field, the sender recovered from the signature, the decoded function call and warnings for unlimited approvals and delegations. All envelopes, from legacy to EIP-7702.
Open toolEIP-7702 Delegation Decoder
Who delegates to which contract
Paste a type-4 transaction, authorization tuples, the message a wallet asks you to sign or an account’s code. See which account delegates to which contract, whether clients apply each authorization, and whether the delegate is a known wallet or a known sweeper.
Open toolEthereum Nonce Reuse Checker
Find repeated r in Ethereum signatures
Scan the transactions an Ethereum address sent, or paste signed transactions, and see whether any two signatures share an r value — the mistake that exposes the private key. Reports exposed keys, tiny nonces and r values shared between keys, and never computes a key.
Open toolBitcoin Message Verifier
Verify BIP-137 and BIP-322 signatures
Check that the holder of a Bitcoin address signed a message: legacy BIP-137 signatures (Bitcoin Core, Electrum, Trezor, Ledger) and BIP-322 simple and full signatures for every address type, including SegWit, Taproot and multisig.
Open toolPSBT Inspector
Decode and check a PSBT before signing
Paste a partially signed Bitcoin transaction and see every field named, what each input spends, where the coins go, which output is change, the fee and fee rate, whether the partial signatures verify, and what a signer should refuse.
Open toolxpub Inspector
Derive addresses from an xpub
Paste an extended public key (xpub, ypub, zpub, tpub and their multisig siblings) to see what it encodes, derive its receive and change addresses for every script type it allows, convert it between SLIP-132 versions and build output descriptors.
Open toolSolana Message Verifier
Verify Solana signed messages
Check an Ed25519 signature of a Solana wallet over a message: bytes signed with signMessage by Phantom, Solflare or Backpack, the CLI’s sign-offchain-message, off-chain messages v0 and v1 and signed envelopes, and Sign-In With Solana.
Open toolNostr Event Verifier
Verify Nostr events and decode npub
Paste a Nostr event or an EVENT message from a relay: the verifier recomputes the id, checks the Schnorr signature and tells an event modified after signing from a wrong id or a forged signature. It also decodes npub, note, nprofile, nevent and naddr.
Open tool