# Ethereum Classic (ETC) Quantum Readiness Report

> Ethereum Classic has a QRI score of 15.75/100 and is assessed at Stage 2 (Mitigation / Development) with medium evidence confidence.

Evaluation date: 2026-06-02. Review status: draft. Evaluated scope: Native asset (ETC) on Ethereum Classic mainnet (Chain ID 61), PoW EVM layer-1, as of 2026-06-02.

Ethereum Classic (ETC) is a proof-of-work EVM layer-1 blockchain whose base-layer spend authorization relies entirely on ECDSA over secp256k1, which is vulnerable to Shor's algorithm. All Externally Owned Accounts (EOAs) that have ever sent a transaction have their public keys permanently exposed on-chain, creating a large pool of long-exposure quantum-vulnerable value (~$1.25B circulating market cap). A draft proposal (ECIP-1122, January 2026) and prototype Core-Geth PR exist for an ML-DSA signature-verification precompile, but this would only enable smart-contract-level PQ verification—it cannot migrate base-layer EOAs or protect the native ETC asset from quantum key-recovery attacks. A core contributor publicly stated the project is in a 'funding crisis with its deprecated client in maintenance mode.' No production PQ or hybrid protection exists. The strict immutability ethos ('Code is Law') creates a further governance obstacle to any state intervention that might be needed to handle dormant or lost accounts with exposed public keys. The QRI Score of 16 reflects the presence of a draft mitigation proposal (Stage 2) combined with near-total absence of production protection, migration coverage, or quantum preparedness. Structural advantages include quantum-safe Keccak-based state integrity and PoW consensus without validator signatures.

## Core resources

- [Ethereum Classic QRI report](https://qrindex.org/projects/ethereum-classic/): Human-readable assessment with score, stage, evidence, blockers, risks, and assurance notes.
- [Ethereum Classic structured report data](https://qrindex.org/projects/ethereum-classic/report.json): Complete report as JSON for deterministic machine processing.
- [QRI methodology](https://qrindex.org/methodology/): Scoring model, evidence handling, readiness stages, confidence, assurance, and report status.
- [All QRI project reports](https://qrindex.org/llms.txt): Score-ranked index of every published project assessment.
- [Ethereum Classic official website](https://www.coingecko.com/en/coins/ethereum-classic): Project-maintained website.



## Evidence sources

- [Evidence source 1](<https://ethereumclassic.org/>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 2](<https://github.com/orgs/ethereumclassic/discussions/556>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 3](<https://github.com/ethereumclassic/ECIPs>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 4](<https://ethereumclassic.org/blog/2018-03-15-signatures/>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 5](<https://dev.to/q9/ethereum-2-part-series-1-accounts-keys-and-addresses-122l>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 6](<https://en.wikipedia.org/wiki/Ethereum_Classic>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 7](<https://github.com/ethereumclassic/ECIPs/blob/master/_specs/ecip-1121.md>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 8](<https://github.com/ethereumclassic/core-geth>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 9](<https://www.coingecko.com/en/coins/ethereum-classic>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 10](<https://coinmarketcap.com/currencies/ethereum-classic/>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 11](<https://github.com/ethereumclassic/ECIPs/pull/557>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 12](<https://eips.ethereum.org/EIPS/eip-8051>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 13](<https://ethereumclassic.com/olympia/security>): Public source cited by the Ethereum Classic QRI assessment.
- [Evidence source 14](<https://github.com/ethereumclassic/core-geth/pull/5>): Public source cited by the Ethereum Classic QRI assessment.