Monad

Is Monad quantum-safe?

Where we are making a judgement call The tier is a judgement call. The Monad Foundation has published a post-quantum roadmap, and Category Labs, which builds Monad, has a Draft proposal that names ML-DSA. A reader who combines the two, treating the roadmap as the plan and the draft as its named scheme, would place Monad in Tier 3, raising the deployment score from 2 to 5 and the Hardy Score by 7.5 points. We read them separately, because the roadmap itself names no scheme, and a draft that lists ML-DSA among possible schemes without a parameter set is not a plan to adopt it.

At a glance

Cryptography in use

• Account signatures ECDSA on secp256k1 Mainnet, default Source code or release
• Validator consensus BLS signatures on BLS12-381 Mainnet, mandatory Votes and timeouts, aggregated into certificates. Specification or proposal
• Validator consensus ECDSA on secp256k1 Mainnet, mandatory The node's signature type is monad_secp::SecpSignature, ECDSA on secp256k1, used for message integrity and authenticity on consensus messages that are not aggregated; the documentation says ECDSA without naming the curve. Source code or release
• Contract level ECDSA on secp256r1 Mainnet, opt-in P-256 precompile at 0x0100 (EIP-7951), used by smart accounts for passkeys. Specification or proposal
• Account signatures ML-DSA Proposed Listed as an initial scheme identifier in a Draft proposal; no parameter set named. Specification or proposal

A role not listed is not evidenced either way. Every scheme, and which other chains share it, is in the cryptography registry.

Score breakdown

How it compares

Roadmap

1. November 2025 shipped

   Monad public mainnet goes live as an EVM-compatible chain, reported in press coverage as launching on 24 November 2025. Monad's documentation lists it as chain ID 143, with accounts signed by ECDSA on secp256k1. source

2. 21 August 2026 shipped

   Kushal Babel and Jan Camenisch of Category Labs post Flexible and Upgradeable Account Authentication to the Monad forum as a Draft: addresses fixed at creation, authenticators that can be added, rotated and retired, and ML-DSA among the initial schemes. source

3. 28 September 2026 shipped

   The Monad Foundation publishes Monad's post-quantum roadmap, ordering the work from wallet authentication and consensus through staking, the EVM, proof infrastructure and the encrypted mempool. It names no scheme and no Monad date. source

4. Ongoing in-progress

   Work on a post-quantum version of Cadence, part of Monad's consensus layer, runs in parallel with the account work. No scheme has been published for it. source

5. No date published proposed

   A concrete implementation specification for account authentication, a selected post-quantum scheme, and any testnet or mainnet deployment. None has been published. source

If holders never migrate

No stated policy

Neither the Draft authentication proposal nor the Monad Foundation's post-quantum roadmap says what happens to accounts that never add a post-quantum key. The proposal leaves existing accounts working as single-key ECDSA accounts, with no sunset.

As of 22 October 2026. source Published beside the score, not in it. Every chain's stance is compared on the commitments page.

Exposure

Exposure measures how much of the chain's value already sits behind a public key that an attacker can record today and break later. This is the part of the threat that a future upgrade cannot undo.

Monad keeps Ethereum's address model: an address is the last twenty bytes of the Keccak hash of the public key, so an account that has never signed has not published its key. That protection ends when the account signs, and accounts in active use have. Monad adds a wrinkle of its own: because it accepts the same keys and addresses as Ethereum, a holder who reuses a key that has already signed on Ethereum or another EVM chain has a published key on Monad too, even if the Monad account has never sent a transaction. The Draft authentication proposal would keep addresses fixed, so it would not change which keys are public, but it would let an exposed account stop accepting its classical key.

Questions

Sources

1. Flexible and Upgradeable Account Authentication Monad forum · primary · checked 22 October 2026
2. Monad's post-quantum roadmap Monad Foundation · primary · checked 22 October 2026
3. Monad Ecosystem Highlights: August 2026 Monad Foundation · primary · checked 22 October 2026
4. ecrecover implementation, Monad execution client Category Labs (GitHub) · primary · checked 22 October 2026
5. Consensus authentication Monad documentation · primary · checked 22 October 2026
6. monad-node-config signature types, Monad consensus client Category Labs (GitHub) · primary · checked 22 October 2026
7. Precompiles Monad documentation · primary · checked 22 October 2026
8. Network information Monad documentation · primary · checked 22 October 2026
9. Jan Camenisch Category Labs · primary · checked 22 October 2026
10. FIPS 204: Module-Lattice-Based Digital Signature Standard (ML-DSA) NIST · primary · checked 22 October 2026
11. Network Information: Mainnet Monad Documentation · primary · checked 22 October 2026

@misc{hardyindex_monad_2026,
  author       = {{The Hardy Index}},
  title        = {Monad: quantum readiness assessment},
  year         = {2026},
  howpublished = {\url{https://hardyindex.com/chains/monad}},
  note         = {Hardy Score 20.0 of 100, Tier 4: Debating. Methodology v1.8},
  urldate      = {2026-11-13}
}