Chain profile
A Bitcoin-derived chain using ECDSA on secp256k1 with no published post-quantum roadmap, though its MWEB soft fork proves it can enact consensus changes Bitcoin has not managed.
No. Litecoin is derived from Bitcoin's codebase and signs with ECDSA on the secp256k1 curve, which a sufficiently large quantum computer would break. We found no published post-quantum roadmap or named replacement scheme for Litecoin at the time of writing. Litecoin does have one advantage that is easy to overlook and that this index credits: it has demonstrated that it can actually ship a significant consensus change. The MWEB soft fork, activating the Mimblewimble Extension Blocks upgrade, was proposed, implemented and activated on Litecoin while comparable proposals on Bitcoin remained unactivated. Governance capability is a real component of migration feasibility, and Litecoin has evidence for it where most chains have only assertions.
Where we are making a judgement call Litecoin sits in Tier 5 because its mainnet signatures are quantum-vulnerable and no post-quantum proposal or roadmap specific to Litecoin was found. Its migration score of 2 is higher than several peers with identical cryptography, and that is deliberate: activating MWEB is evidence that Litecoin can enact a consensus change, which is the capability a quantum migration would ultimately require.
ECDSA on secp256k1, inherited from Bitcoin
None proposed. No Litecoin-specific post-quantum work was found.
None adopted
Tier 5: Exposed. The signatures securing funds on mainnet today are quantum-vulnerable, and no public post-quantum plan, proposal or research programme could be found.
| No. | Dimension | Score | Weight | Contribution |
|---|---|---|---|---|
| 1 | Signature scheme | 0 | 30% | 0.0 |
| 2 | Deployment stage | 1 | 25% | 2.5 |
| 3 | NIST alignment | 0 | 15% | 0.0 |
| 4 | Migration path | 2 | 15% | 3.0 |
| 5 | Exposure | 4 | 10% | 4.0 |
| 6 | Verification | 6 | 5% | 3.0 |
| Hardy Score | 12.5 | |||
Litecoin uses ECDSA on secp256k1, inherited from the Bitcoin codebase. Nothing post-quantum protects LTC on mainnet. source
Tier 5: Exposed. Litecoin signs with ECDSA on secp256k1 and no post-quantum proposal or roadmap specific to Litecoin was found at the time of writing. source
No post-quantum scheme has been named or proposed for Litecoin, so there is nothing to assess against a NIST standard. source
Litecoin has demonstrated it can activate a substantial consensus change, having shipped the MWEB soft fork, which is direct evidence of governance capability rather than a claim about it. It has not applied that capability to the quantum problem, and no migration plan exists. source
Litecoin uses the UTXO model with addresses derived from public key hashes, so unspent coins have not published a key. Spending reveals it, and address reuse is common, so a meaningful share of supply sits behind revealed keys. source
The Litecoin client is open source and derived from a heavily reviewed codebase, so the signature scheme can be verified directly. There is no post-quantum claim to assess. source
The deployment dimension is not a separate judgement. It is Tier 5 expressed as a number. See the tier mapping.
Litecoin activates the MWEB soft fork, demonstrating that it can propose, implement and activate a substantial consensus change. Not post-quantum work, but directly relevant evidence of migration capability. source
No post-quantum roadmap or improvement proposal specific to Litecoin was found at the time of writing. source
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.
Litecoin follows Bitcoin's UTXO model, so an address is a hash of a public key and the key is published only when an output is spent. Coins received and never moved are not harvestable. As on Bitcoin, that protection erodes through address reuse and ordinary spending, and Litecoin has a long transaction history in which many addresses have been reused. Unlike Bitcoin, no independent analysis quantifying the share of Litecoin supply behind revealed keys was found, so the exposure score here reflects the address model rather than a measurement.
What this rating means for you
Litecoin runs quantum-vulnerable signatures with no published post-quantum plan that we could find. Nothing here is urgent today, and there is also nothing scheduled to change it.
Editorial guidance from the Hardy Index. Nothing on this profile is sponsored and nothing on it is an affiliate link. The guides carry disclosed affiliate links, which never affect a rating. How we make money.
No. Litecoin uses ECDSA on the secp256k1 curve, inherited from Bitcoin, which a sufficiently large quantum computer would break. We found no published post-quantum roadmap or proposal specific to Litecoin.
Because it has proved it can ship a consensus change. Litecoin proposed, implemented and activated the MWEB soft fork, while comparable proposals on Bitcoin remain unactivated. That is evidence of governance capability rather than an assertion, and migration feasibility is partly a governance question.
No. MWEB is a privacy and scaling upgrade based on Mimblewimble. It does not change the signature scheme protecting funds, which remains ECDSA on secp256k1. Privacy and quantum safety are separate properties, and MWEB delivers the first without affecting the second.
Plausibly. Litecoin's codebase is closely derived from Bitcoin's, so an output type such as the one proposed in BIP-360 could be adapted rather than designed from scratch. Combined with Litecoin's demonstrated ability to activate soft forks, that is a credible route, though no one has published a plan to take it.
This is a security-readiness assessment, not investment advice.