Blockchain Encoding Tools

Free online blockchain encoding tools — a Keccak-256 hash generator computed entirely client-side. Nothing you paste is ever sent to a server.

8 tools

RLP Encoder

Decode a raw Ethereum RLP payload into its fields, or serialise a nested structure back into bytes. Shows every item, length prefix and nesting level.

Base58 Encoder

Encode bytes or text to Base58 and Base58Check, or decode a Base58 string back to hex with a full checksum check. Runs entirely in your browser.

Keccak-256

Compute the Keccak-256 hash of text or raw hex bytes entirely in your browser — the Ethereum variant, not NIST SHA-3. No uploads, ever.

EIP-55 Checksum

Apply or validate the EIP-55 mixed-case checksum on any Ethereum address. Shows checksummed, lowercase, and uppercase forms with instant copy.

Satoshi/BTC

Convert between Satoshi, Bit, mBTC and BTC with BigInt precision. No floating-point rounding at the satoshi level, no price feed, no network call.

Also in Blockchain Encoding

Tools from other categories tagged with Blockchain Encoding

BTC Validator

Check any Bitcoin address for a valid checksum and see its type, network and witness program. Legacy, SegWit and Taproot, all offline.

ENS Namehash

Compute the ENS namehash (EIP-137) for any .eth domain, label by label, using Keccak-256 in your browser. See every recursive hashing step.

Merkle Tree Builder

Build a Keccak-256 Merkle tree from an address allowlist, read off the root, and copy an inclusion proof for any leaf. OpenZeppelin sorted pairs.

Why These Tools

Keccak-256 Hash Generator and EIP-55 Checksum Tool are the first two tools in a category built around the encoding layer that underpins every Ethereum operation. The hash generator exists because the Keccak used by Ethereum pads its input differently from NIST SHA-3, and mixing the two up is an easy way to spend an hour debugging a hash mismatch that was never a bug. The checksum tool applies the EIP-55 mixed-case rule that encodes that same Keccak-256 hash into the capitalisation of an address, so a single mistyped character fails validation instead of silently routing funds to the wrong destination. Both tools use the same verified Keccak-256 implementation that also backs the Function Selector Calculator. RLP encoding and Base58/Bech32 address tooling are next.