Bitcoin Stamps are a way to tuck extra data into Bitcoin transactions so that the information sticks around on the blockchain. Instead of living off-chain or in a database that can be altered, the data is preserved inside Bitcoin’s transaction structure, which gives it strong permanence. The method emerged as an alternative to inscription style systems and focuses on keeping the data unprunable and easy to verify later.
How the technique works
In the Stamps approach, creators convert content like small images into a base64 string and place that string inside parts of a Bitcoin transaction linked to unspent transaction outputs, or UTXOs. Because UTXOs are part of Bitcoin’s spendable state, nodes retain them, which helps the data stay persistent. The entries are also organized by timestamp, which lets services display or index them in order.
Some explanations also describe using Bitcoin’s capability to include arbitrary data in transactions. That lens helps newcomers understand the basic idea: you broadcast a normal transaction that includes a tiny payload, miners confirm it, and the added data becomes part of the chain’s history.
Ordinals inscriptions attach data in the witness area of a transaction. Nodes can run in modes that prune or skip certain historical witness data to save space, which may reduce long-term availability. Stamps put their payload in UTXOs, which full nodes keep for validation, so the content is designed to be non-prunable. That difference is why Stamps are often pitched for long-lived records while Ordinals are seen as more space efficient but less rigid about permanence.
SRC-20 tokens. Developers created a fungible token format called SRC-20 that uses Stamps to anchor token data on UTXOs. Fees are paid in BTC, and the design targets immutability of the underlying metadata. It is frequently contrasted with BRC-20, which uses Ordinals and the witness field rather than UTXOs.
SRC-721. Another specification aims at composable, high-resolution NFTs built on the same Stamps foundation. It focuses on layered storage and compact files while using Counterparty asset identifiers for stability.
Practical uses
Since the data is meant to be durable, Stamps show up in contexts where you want proof that something existed at a particular time. Examples include certificates, historical snapshots, simple digital artworks, and other records that benefit from long-term authenticity on a public ledger.
Relying on UTXOs helps with permanence, but large payloads will raise transaction costs. BRC-20 has gathered more listings and wallet integrations so far, while SRC-20 and other Stamps-based projects are still growing their tooling and support. The choice between the two often comes down to whether you value wider adoption and cheaper witness space or stronger guarantees around unpruned storage.