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What are Runes?
Runes is a protocol for creating, minting and transferring fungible tokens directly on Bitcoin. Unlike an inscription, every unit of a rune is the same as every other, so runes work like tokens rather than collectibles.
What it means for you
Runes live inside ordinary Bitcoin transaction outputs, so a wallet that does not understand them can spend them by accident, as fees or in a normal payment. A malformed rune message burns the runes involved. Use a wallet that says it supports Runes before holding any.
A common mistake: “THORChain's RUNE token is one of the Runes.”
In fact: They share a word and nothing else: RUNE is the coin of a separate network, while Runes are tokens created on Bitcoin with the Runes protocol.
How it works
Rune messages, called runestones, are written into a Bitcoin transaction output that begins with OP_RETURN followed by OP_13. Etching creates a rune and fixes its properties for good: a name of 1 to 26 letters, its divisibility, a symbol, an optional premine and the terms for minting. While a rune's mint is open, anyone can send a mint transaction that creates a fixed amount of new units. Balances sit on transaction outputs, one output can hold any number of runes, and transfers move them from inputs to outputs. A malformed runestone, called a cenotaph, burns the runes in that transaction. Runes are numbered by the block and transaction that etched them.
Source: Ordinal Theory Handbook: Runes · checked 5 October 2026
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