NIP-05 checker
Validate a name@domain Nostr identifier end-to-end:
URL format, HTTPS, redirects, CORS headers, JSON shape, pubkey
format, advertised relays. Real npub bech32 output.
Free tools
Public, no-signup utilities for Bitcoin, Nostr, and Lightning. Sensitive Bitcoin tools run locally whenever possible, and inputs are never retained.
LNURL decoder
Decode any LNURL bech32 string, lightning address, or LNURL URL,
then fetch and pretty-print the response: payRequest,
withdrawRequest, login,
channelRequest.
Nostr key generator
Generate a fresh Nostr keypair (priv/pub hex, nsec,
npub, nprofile) entirely in your
browser. Optional vanity-prefix search via Web Worker. Nothing
is sent or stored.
Bitcoin address inspector
Validate mainnet, testnet, signet, or regtest addresses and inspect their script type, scriptPubKey, and descriptor hint.
Bitcoin fee planner
Compare transaction fees and calculate RBF or CPFP targets locally in your browser without sharing wallet data.
Raw transaction decoder
Decode transaction hex, inspect inputs and outputs, identify RBF signaling, and flag dust without broadcasting anything.
Descriptor import generator
Build Bitcoin Core importdescriptors JSON locally
from a public descriptor, range, timestamp, and label.
PSBT inspector
Inspect PSBT inputs, outputs, UTXO metadata, signatures, fees, and completeness locally without signing or uploading the file.
Transaction planner
Calculate fees, recipients, change, and dust from explicit UTXOs entirely in your browser.
Xpub address explorer
Derive BIP44, BIP49, BIP84, and BIP86 watch-only receive and change addresses with no blockchain lookup.
Bitcoin QR generator
Generate local QR images for addresses, BIP21 URIs, xpubs, descriptors, and small PSBT payloads.
BIP39 wallet generator
Generate a mnemonic and BIP44, BIP49, BIP84, or BIP86 addresses entirely in your browser. Offline use is strongly recommended.
Unsigned PSBT builder
Build a BIP174 PSBT from explicit UTXOs, recipients, change, fee rate, and size entirely in your browser.
BIP39 recovery checker
Validate an existing mnemonic and derive BIP44, BIP49, BIP84, or BIP86 watch-only addresses locally without exposing seed material.