---
title: "sr25519: which blockchains use it"
url: "https://hardyindex.com/algorithms/sr25519"
---

# sr25519

Schnorr signatures over the Ristretto-compressed Curve25519 group, the Substrate default used by Polkadot and chains built on its framework. It has no formal standard. Broken by Shor's algorithm on a cryptographically relevant quantum computer, which recovers the private key from the public key.

- **Quantum status:** Broken by Shor's algorithm on a cryptographically relevant quantum computer.
- **Standard:** No published standard.
- **Family:** elliptic curve.
- **Also known as:** Schnorrkel, Ristretto Schnorr.

## Rated chains using it

- [Bittensor](https://hardyindex.com/chains/bittensor.md): account signatures, mainnet, default. Coldkeys and hotkeys. Source (statement or write-up): https://bittensor.com/docs
- [Midnight](https://hardyindex.com/chains/midnight.md): validator consensus, mainnet, mandatory. Aura block-authoring keys. MIP-0010, with status Proposed, would move block production to BABE, also on sr25519. Read at the node-1.0.400 release tag, which Midnight's release notes tell every Mainnet node to run; its runtime is spec version 1.0.300. Source (source code or release): https://github.com/midnightntwrk/midnight-node/blob/node-1.0.400/runtime/src/lib.rs
- [Polkadot](https://hardyindex.com/chains/polkadot.md): account signatures, mainnet, default. Source (specification or proposal): https://wiki.polkadot.com/learn/learn-cryptography/

## Sources

- [Cryptography on Polkadot](https://wiki.polkadot.com/learn/learn-cryptography/), Polkadot Wiki. Accessed 19 October 2026.