---
title: "SLH-DSA: which blockchains use it"
url: "https://hardyindex.com/algorithms/slh-dsa"
---

# SLH-DSA

The Stateless Hash-Based Digital Signature Algorithm, standardised by NIST as FIPS 205 in August 2024 from SPHINCS+. Its security rests on hash functions alone, at the cost of large signatures.

- **Quantum status:** Believed quantum-resistant. No post-quantum scheme carries a proof of resistance.
- **Standard:** FIPS 205 (NIST, final).
- **Family:** hash based stateless.
- **Also known as:** SPHINCS+, FIPS 205.

## Rated chains using it

- [Aptos](https://hardyindex.com/chains/aptos.md): account signatures, specified, not deployed, SLH-DSA-SHA2-128s. Opt-in alongside Ed25519 under AIP-137, accepted April 2026. Merged and enabled on devnet only (feature flag 107); off on testnet and mainnet as read on 22 October 2026. Source (source code or release): https://github.com/aptos-labs/aptos-core/pull/18300
- [IOTA](https://hardyindex.com/chains/iota.md): identity layer, mainnet, opt-in. IOTA Identity v1.7 credentials, not layer-1 transactions. Source (specification or proposal): https://docs.iota.org/developer/iota-identity/how-tos/post-quantum
- [Nervos CKB](https://hardyindex.com/chains/nervos-ckb.md): account signatures, mainnet, opt-in, SPHINCS+, twelve parameter sets. Through an audited lock script. Source (specification or proposal): https://docs.nervos.org/docs/ckb-features/native-quantum-resistance
- [Sui](https://hardyindex.com/chains/sui.md): contract level, proposed, SLH-DSA-SHA2-128s. Smart contract vaults. Source (statement or write-up): https://www.sui.io/blog/making-sui-quantum-ready

## Sources

- [FIPS 205: Stateless Hash-Based Digital Signature Standard](https://csrc.nist.gov/pubs/fips/205/final), NIST. Accessed 19 October 2026.