Cryptography tools

Hashing, encryption, encoding and address tools that run entirely in your browser — fast, free, and private.

🔒 100% in your browser — nothing is uploaded

• Hash Generator

  Hash generator online for SHA-256, SHA-512, Keccak-256, RIPEMD-160 and MD5, from text or hex. Runs in your browser — nothing is ever uploaded.

• AES Encryption

  AES encryption online with AES-GCM and a password-derived key. Encrypt and decrypt text in your browser via WebCrypto — nothing is uploaded.

• Crypto Address Validator

  Crypto address validator for Bitcoin and Ethereum: checks the checksum, the format and the network, and tells you which one it is. Free, in-browser.

• Base64, Hex & Base58 Converter

  Base64, hex and base58 converter in one place, plus UTF-8 and binary. Convert between any pair in your browser — nothing leaves your machine.

• BIP39 Seed Phrase Generator

  BIP39 seed phrase generator and validator: 12 or 24 words, with checksum verification and the derived seed. Generated in your browser, never sent.

• Password Generator

  Password generator using your browser's own CSPRNG: length, character sets and an entropy readout in bits. Nothing is uploaded or stored anywhere.

• JWT Decoder

  JWT decoder for header, payload and signature, with expiry and issued-at rendered as real dates. Decodes in your browser — no token is ever uploaded.

• HD Wallet Address Generator

  HD wallet address generator: a BIP39 mnemonic to BIP32/44/84 addresses with the derivation path shown. Derived in your browser, never transmitted.

• RSA Key Generator

  RSA key generator for 2048, 3072 and 4096-bit keypairs in PEM, via your browser's WebCrypto. The private key is generated locally and never leaves it.

• Message Signer & Verifier

  Sign and verify a message with secp256k1 ECDSA, the Bitcoin and Ethereum way. Signed in your browser — the private key never leaves your machine.

• Crypto QR Code Generator

  Bitcoin QR code generator for addresses and BIP21 payment URIs, with an amount and label. Rendered in your browser — no address is ever uploaded.

• Merkle Tree Calculator

  Merkle root calculator: paste leaves, get the root and the full SHA-256 tree with every proof path. Computed in your browser, nothing uploaded.

• EVM Bytecode Disassembler

  EVM bytecode disassembler: paste hex, get readable opcodes with push data and jump destinations resolved. Runs in your browser, free, no sign-up.

• Vanity Address Generator

  Vanity address generator for Ethereum: pick a prefix and grind it in your browser with Web Workers. The key is generated locally and never sent.

• Ethereum Function Selector

  Ethereum function selector and event topic calculator: paste a signature, get the 4-byte selector and the keccak256 topic. Free and in-browser.

• ENS Namehash Calculator

  ENS namehash calculator: get the namehash and labelhash for any .eth name, with every level of the recursion shown. Computed in your browser, free.

• Proof-of-Work Mining Simulator

  Proof of work demo: pick a difficulty and watch the nonce grind until the hash beats the target. Mining made visible, in your browser, free.

• EIP-712 Typed Data Hasher

  EIP712 hash calculator for typed structured data: paste the JSON, get the domain separator, struct hash and final digest. Runs in your browser.

• Elliptic Curve (ECC) Visualizer

  Elliptic curve visualizer for point addition and doubling over a small prime field. See why ECC works, plotted point by point, in your browser.

• Shamir Secret Sharing

  Shamir secret sharing in your browser: split a secret into N shares needing M to rebuild, then recombine them. Nothing is uploaded, ever.

• Ethereum Transaction Decoder

  Raw transaction decoder for Ethereum: paste RLP hex to get every field plus the recovered sender address. Decoded in your browser, never uploaded.