Output descriptor

Also called: output script descriptor, descriptor, wallet descriptor, descriptors, descriptor wallet, wpkh(), tr().

An output descriptor is a short text string that says exactly which scripts and addresses a wallet uses: script type, keys and derivation paths.

An output descriptor (in full, an output script descriptor) is a compact, human-readable description of a set of Bitcoin output scripts. It records the three things a seed phrase leaves out: the script type, the keys involved and their derivation paths.

What one looks like

wpkh([d34db33f/84h/0h/0h]xpub6.../0/*)#checksum

wpkh(...) is the script expression: native SegWit P2WPKH.
[d34db33f/84h/0h/0h] is the key origin: the master key's fingerprint and the path to the account.
xpub6... is the account xpub, and /0/* means every receiving address below it.
#checksum is an 8-character checksum that catches typos.

Other expressions include pkh(), sh(), wsh(), multi(), sortedmulti(), tr() and multi_a(), and they nest: sh(wpkh(...)) is wrapped SegWit and wsh(sortedmulti(2,...)) with three keys is a 2-of-3 multisig.

The BIPs

Pieter Wuille and Ava Chow specified descriptors as a family: BIP 380 (syntax, key expressions and checksums), BIP 381 to BIP 385 (legacy, SegWit, multisig, combo(), raw() and addr()), BIP 386 (tr() for Taproot) and BIP 387 (multi_a() for tapscript multisig). BIP 389 proposes /<0;1>/* to cover receive and change addresses in one descriptor, and Miniscript (BIP 379) extends the language to complex spending policies.

Why it matters

A descriptor plus its keys is a complete wallet backup: any compatible wallet can find every address without guessing paths or script types. Bitcoin Core's wallet is built on descriptors. Read the output descriptors guide.

BIPs that define Output descriptor

BIP 380: Output Script Descriptors General Operation: Deployed. Output script descriptors are a compact text language for describing exactly which addresses a wallet owns and how they are spent. This document defines their general syntax and checksum, giving…
BIP 382: Segwit Output Script Descriptors: Deployed. Defines the descriptor functions for native SegWit outputs, covering both single-key addresses and script-based ones. With these, wallets can precisely describe and back up SegWit wallets, including…
BIP 386 (Taproot descriptors): tr() Output Script Descriptors: Deployed. Defines the descriptor function for Taproot outputs, combining a main key with an optional tree of alternative spending conditions. This gives wallets a standard way to describe, back up and recover…
BIP 383: Multisig Output Script Descriptors: Deployed. Defines descriptor functions for multisignature setups, where a certain number of keys out of a group must sign. One version keeps keys in the given order and another sorts them automatically, which…
BIP 381: Non-Segwit Output Script Descriptors: Deployed. Defines the descriptor functions for Bitcoin's older address types: pay-to-public-key, pay-to-public-key-hash (classic addresses starting with '1'), and pay-to-script-hash (addresses starting with…
BIP 385: raw() and addr() Output Script Descriptors: Deployed. Defines two simple descriptor functions: one that wraps an arbitrary raw script and one that wraps a plain address. They let wallets track coins in formats not otherwise covered, or watch an address…
BIP 387: Tapscript Multisig Output Script Descriptors: Deployed. Defines descriptor functions for multisignature setups inside Taproot scripts, which require a different construction than older multisig. One form keeps keys in the given order and the other sorts…
BIP 389: Multipath Descriptor Key Expressions: Draft. Extends descriptors so one key expression can represent several related derivation paths at once, such as a wallet's receiving and change addresses. This shortens wallet backups and avoids having to…

Related terms

Miniscript: Miniscript is a structured way to write Bitcoin Script, specified in BIP 379, that makes complex spending conditions easy to analyze, combine and sign.
xpub (extended public key): An xpub is a BIP 32 extended public key: a public key plus chain code that can derive every address in an account, but can't spend from them.
Derivation path: A derivation path like m/84'/0'/0'/0/0 locates one key inside an HD wallet: the sequence of child indexes taken from the master key.
Multisig: Multisig (multi-signature) locks bitcoin so that M of N chosen keys must sign to spend it, for example any 2 of 3 keys kept in different places.
Seed phrase: A seed phrase is a list of 12 to 24 words, defined by BIP 39, that encodes the random number from which a wallet derives all of its keys.