What it is
This site started as a crypto payment QR code generator: it turns a receiving address, a Lightning invoice or a Lightning address into a scannable payment code, because most wallets only show a QR code on a phone screen, which is awkward to print, embed on a website or send to a customer who will pay later. It has since grown into a set of developer tools: address validators and converters, exact unit converters, Keccak-256 and ABI utilities, bech32 and hex helpers, raw transaction decoders for Ethereum, Bitcoin, Solana and Tron, and testnet batch-transfer tools.
How it works
Every tool is plain JavaScript running in your browser. The payment pages build a standard link (BIP-21 for Bitcoin, EIP-681 for Ethereum and ERC-20 tokens, Solana Pay for Solana, LNURL for Lightning addresses) and draw it as a QR code. The decoders and validators implement the relevant standards directly (Base58Check, bech32 and bech32m, EIP-55, RLP, Solana message layout, Tron protobuf) so nothing has to be sent to a server. There is no backend, no database and no account system. If you load a page and switch off your connection, it still works. The only exception is the batch-transfer pages, which must talk to your wallet and a public testnet RPC to send transactions.
What it is not
This is not a wallet, a payment processor or an exchange. It never holds funds, never generates, asks for or stores seed phrases or private keys, and cannot see or reverse transactions. A payment QR code only contains a public receiving address, which is safe to share.
Who builds it
The site is built and maintained by an independent developer with a background in wallet security and blockchain infrastructure. It is supported by unobtrusive advertising so it can stay free. The decoders and validators are checked against test vectors from the official specifications and against live transactions from each network. Bug reports and feature requests are welcome through the contact page.