Layer 1 blockchain
Ethereum Classic ticker ETC
Summary
Ethereum Classic is a proof-of-work chain that runs the EVM over an account model. Miners search for a block whose Etchash proof of work meets the current difficulty. Etchash is the memory-hard Ethash (Dagger Hashimoto) algorithm with its epoch length doubled to 60,000 blocks at block 11,700,000 (the Thanos upgrade, November 2020, ECIP-1099), which slows growth of the mining dataset. ECIP-1017 sets issuance: the block reward falls by 20% every 5 million blocks, plus small uncle rewards. Protocol changes are written as ECIPs and take effect at named hard-fork blocks; the latest, Spiral, activated at block 19,250,000 in February 2024. Two reads of Blockscout's stats API on 2026-09-29 gave average block times of 14.9 and 13.9 seconds. 89101213182134
Design
- System
- Layer 1 blockchainIndependent, permissionless proof-of-work chain with its own miners; it does not settle to another chain. It shares its history with Ethereum up to block 1,920,000 and continued without the DAO-recovery hard fork of 20 July 2016. It runs the EVM under chain ID 61, and no rollup or sidechain anchored to it was found.
- Settlement family
- Ethereum / EVM
- Scarce resource
- Work (proof of work)
- State model
- Accounts
- Finality
- Probabilistic
- Who makes blocks
- Miners, many through pools, propose blocks by finding Etchash proofs; anyone with suitable GPU or ASIC hardware can mine without permission. Two blocks read on 2026-09-29 carried the extra-data tag of K1Pool; pool shares were not measured. Every full node checks each block itself. Core-Geth runs on almost every node: its v1.13.0 release notes count 524 Core-Geth nodes of 550 seen by etcnodes.org on 17 September 2026. Fukuii, an independent Scala client, last made a full release in July 2026 (later builds are pre-releases), and Besu dropped Ethereum Classic in 26.2.0 (March 2026).
- Fork choice
- Nodes follow the valid chain with the greatest total difficulty. Core-Geth adds MESS, a client-side rule that asks a competing chain for more total difficulty the older its fork point is, without changing block validity. MESS became the default in October 2020 after reorganization attacks, was switched off at the Spiral block in February 2024 (ECIP-1110) and applies again by default in Core-Geth v1.13.0 (September 2026). A node drops it with fewer than five peers or a stale head, and nodes with different settings can prefer different chains in a deep reorganization.
Qualifications
- Chain origin · Applies. At block 1,920,000 on 20 July 2016 the chain split: nodes that adopted the DAO-recovery hard fork followed the branch now called Ethereum, and nodes that did not followed the branch now called Ethereum Classic. Blocks before that height are shared. The Die Hard upgrade (block 3,000,000, January 2017) added replay protection with chain ID 61, so transactions signed with it cannot be replayed on the other chain.
- Mess reorg scoring · Contested. MESS is client policy in Core-Geth, not a consensus rule. ECIP-1110, still marked Active, switched it off at block 19,250,000, and the v1.12 release line keeps it off, but Core-Geth v1.13.0 from the ethereumclassic/core-geth repository (September 2026) applies it again by default and lets operators opt out. The documented ECIP and that client default now disagree; Core-Geth's documentation says the status of both MESS documents is open for discussion, and Fukuii's repository describes a MESS implementation of its own. How many miners, pools and exchanges run it was not measured.
- Fee market · Contested. Transactions offer a gas price, and the fee goes to the block's miner; the Mystique upgrade (ECIP-1104, 2022) left out a base-fee market. Draft ECIPs would add one, sending base fees to an on-chain treasury (the Olympia set, ECIP-1111 onward) or to miners (ECIP-1120). None has an activation block, and a March 2026 summary co-written by authors of both approaches presents the question as open.
- Protocol change process · Applies. Changes follow the ECIP process: editors number and merge drafts, discussion runs on development calls, Discord and GitHub, and an ECIP becomes Final after real-world adoption. There is no on-chain vote; a hard fork takes effect when node operators run client releases that set its block. Draft ECIP-1113 and ECIP-1117 propose on-chain treasury governance.
- Client diversity · Partial. Core-Geth, a downstream of go-ethereum, ran on 524 of 550 counted nodes in September 2026. It is published from two repositories: etclabscore/core-geth (the v1.12 line, last release August 2026, commits continuing in September) and ethereumclassic/core-geth, a fork whose v1.13.0 presents itself as the continuation. Besu removed Ethereum Classic support in 26.2.0, and Fukuii's latest full release is v0.8.0 (July 2026), with later builds marked pre-release and no count of nodes running it. Inference: a Core-Geth fault would reach most of the network at once.
- Throughput · Unknown. No primary-source throughput figure was classified. Miners set the block gas limit, and draft ECIP-1130 describes the current limit as well below the per-transaction cap it considered.
Tradeoffs
- Emphasizes
- Decentralization and Security Contested
- Gives up
- Base-layer capacity and settled finality. Miners set the block gas limit, which caps the computation each block can hold (8,000,000 gas in two blocks read on 2026-09-29); blocks arrive about every 14 seconds; and confirmations only grow in confidence. Proof-of-work security depends on how much hash power could be turned against the chain: Ethereum Classic suffered a chain reorganization attack in January 2019 and three more in July and August 2020, and the client-side MESS rule was the response.The security reading is contested: Ethereum Classic's own materials stress proof of work and immutability, while the chain suffered majority-hashrate reorganization attacks in 2019 and 2020, as the trade-off text records. Mining is open, but pool concentration and total hash rate were not measured here. Software diversity is low: one client runs on nearly all counted nodes, and the main change process depends on a small group of client maintainers and ECIP authors.
- Full node at home
- Practical at home 2324Core-Geth's documentation measured a default snap sync on 2026-09-13 (v1.13.0, block 25,337,078) on a 6-core laptop-class CPU with 31 GiB of RAM and an NVMe SSD: 69 minutes, about 51 GiB on disk (read while the state snapshot was still being generated) and a peak of about 2.3 GiB of memory. Full sync and archive needs were not measured, and the chain keeps growing. Snap sync fetches a recent state from peers and executes blocks after that point. Light sync mode is deprecated in Core-Geth.
- Throughput claims
- No classified figure recorded
Scaling layers
No scaling layer recorded in this profile.
Capabilities
| Capability | How it is provided | Notes and sources |
|---|---|---|
| Account abstraction | Structured assessment pending | Not yet assessed for any chain. |
| Atomic swaps | Unknown | Not yet assessed under this row's current definition. EVM contracts can check hash preimages and block times, which are building blocks for hash-time-locked swaps, but no cited source shows a swap tool live on Ethereum Classic mainnet. |
| Authenticated data publication | Unknown | Not yet assessed under this row's current definition. |
| Light clients | Built into the protocolLimited scope | Proof-of-work header chain: consensus produces what a light client checks, since every header carries an Etchash proof of work and nodes follow the valid chain with the most total difficulty. Limited: Core-Geth's documentation says its light sync mode is deprecated and the light flags have no effect, and no other light client was reviewed, so no maintained client for this check was found. 92124 |
| Native staking or delegation | Structured assessment pending | Not yet assessed for any chain. |
| On-chain governance | Structured assessment pending | Not yet assessed for any chain. |
| Parallel execution | Structured assessment pending | Not yet assessed for any chain. |
| Payment or state channels | Unknown | No payment or state channel network running on Ethereum Classic was found in the reviewed sources; EVM contracts could host one. |
| Programmable spending | Native (protocol or core-team software) Earlier definition | Smart contracts run on the EVM, with instruction sets extended through named hard forks up to Spiral (February 2024). Spend rules beyond one signature live in contract accounts; ordinary accounts are controlled by a single key. 21112 |
| Protocol-verified messaging | Structured assessment pending | Not yet assessed for any chain. |
| Reversible transfers or recovery | Unknown | Not yet assessed under this row's current definition. |
| Rollups | None found Earlier definition | The draft Bastion proposal (ECIP-1130, June 2026) defers a feature partly aimed at rollups because, it says, Ethereum Classic has no layer-2 rollup ecosystem to use it; no rollup settling to the chain was found in this review. 16 |
| Shielded transfers | Structured assessment pending | Not yet assessed for any chain. |
| Signed partial offers | Unknown | Not yet assessed under this row's current definition. |
Reading these values
- How this feature is provided
- Built into the protocol, core-team software or independent software says where a feature lives and who can change it. These are implementation layers, not quality: core-team software is not closer to the protocol than independent software.
- Structured assessment pending
- The shared review has not assessed this feature for any chain yet (Account abstraction, Native staking or delegation, On-chain governance, Parallel execution, Protocol-verified messaging and Shielded transfers). That does not mean it is absent, and a chain’s profile may already describe it.
- Unknown
- The review has not established this for this chain under the current definition; the note beside it says why. Unknown is not absent and not a low score. A feature reads “Not present” only when a source shows it is absent.
- Earlier definition
- Payment or state channels, Programmable spending and Rollups keep the earlier definition until the next fact-check. There, “Native” does not separate the protocol from core-team software, “Ecosystem software” does not say who publishes it, and “Partial” does not say which layer.
- Reading across rows
- The list of capabilities is incomplete. Do not read these rows as a chain leading or lagging overall.
Ecosystem & custody
| Product type | Status | Notes and sources |
|---|---|---|
| Automated market makers | ThinETCswap (V2 and V3), HebeSwap, ETCMC DEX | ETCswap's site offers V2 pools and V3 concentrated-liquidity pools for tokens on Ethereum Classic, HebeSwap's site describes an automated market maker created by HebeBlock, and DeFiLlama lists these and other exchanges on the chain. Liquidity depth, operators' controls and audits were not reviewed. 6282930 |
| Issuer-native stablecoins | ThinClassic USD (USC, issued by Brale) | Brale says it issues Classic USD on Ethereum Classic, through a partnership with EthereumClassic.com, as a fiat-collateralized token backed by cash and short-dated US government obligations, with issuance and redemption for businesses in supported jurisdictions. Neither Circle's USDC contract list nor Tether's supported-protocol list includes Ethereum Classic. USC's circulating amount was not verified. 313233 |
| Algorithmic stablecoins | Unknown | DeFiLlama lists Ethereum Classic Stable Dollar, which describes itself as an ETC-backed dual-token stablecoin built on the Djed design, but marks its website as dead; whether it still operates was not verified. 30 |
| Bridges | Unknown | DeFiLlama lists NerveBridge with Ethereum Classic among its chains, and the community apps page lists SwapBox by Nabox, but no bridge operator's own page confirming current Ethereum Classic transfers was read, so no bridge is recorded as live. Risk: Any bridge to or from Ethereum Classic relies on its own operators, relayers or contracts, not on Ethereum Classic miners; no bridge's security model was assessed here. 630 |
| Block explorers | Established in the ecosystemBlockscout (etc.blockscout.com), Blockchair, OKLink, 3xpl | The community explorers page lists these and others as unofficial submissions. Two operators were seen serving current data on 2026-09-29: Blockscout's public API answered, and 3xpl's Ethereum Classic page showed block 25,434,064. An explorer's view is provider-indexed data, not independent validation. 53439 |
| Hardware wallets | Established in the ecosystemLedger, Trezor | See the custody rows: both vendors support ETC in their own wallet apps. 353640 |
Hardware-wallet custody
| Device maker | Status | What users can and cannot do |
|---|---|---|
| Ledger | Native supportSame as native: Unknown | Can: Send, receive and manage ETC in the Ledger Wallet app, signing on the device with the dedicated Ethereum Classic device app named in Ledger's currency list Can: Buy, sell or swap ETC inside Ledger Wallet through third-party providers, per Ledger's Ethereum Classic pageLedger Wallet's current EVM configuration (develop branch, read 2026-09-29) defines Ethereum Classic on chain ID 61, and the network is not among those Ledger Wallet hides behind a feature switch, so it is on by default. Ledger's currency list (@ledgerhq/cryptoassets 13.56.0) records a device app of its own. The marketing page's generic mention of staking was not read as an Ethereum Classic feature. 35363738 |
| Trezor | Native supportSame as native: Unknown | Can: Send and receive ETC in Trezor Suite on desktop, web and mobile with Trezor Safe 3, Safe 5 and Safe 7 Can: Buy, sell and swap ETC through Trezor Suite Can: Use the device with MetaMask or Rabby, which Trezor lists as compatible appsWallets that derive ETC keys under different derivation paths show different addresses for the same recovery phrase, so a restore in another app can look empty; which path each vendor app uses was not checked. 40 |
Public data
iKnow Blockchain has no public-data lookups for Ethereum Classic yet. This is a limit of the service, not a statement about the network.
| Lookup | Status | What it covers and its limits |
|---|---|---|
| Address or account | Not available yet | Public-data lookups for this chain are not built yet. |
| Tokens and assets | Not available yet | Public-data lookups for this chain are not built yet. |
| NFTs | Not available yet | Public-data lookups for this chain are not built yet. |
| Transactions | Not available yet | Public-data lookups for this chain are not built yet. |
Sourced developments
Developments: Reviewed Sep 29, 2026 Next review due Oct 9, 2026, 12:00 UTC.
Publication date · newest first
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Core-Geth v1.13.0 released from the ethereumclassic repository, with MESS on by default
Core-Geth v1.13.0, the first release from the ethereumclassic/core-geth fork, fixes six client vulnerabilities and a GraphQL nesting limit, is built with a current Go toolchain and asks operators to rotate their node key. It removes the ECIP-1110 switch-off, so MESS applies again by default; starts an Ethereum Classic node when no network is named; and ships bootnodes and discovery lists run by its maintainers, saying the ETC Cooperative is winding down and etc.rivet.link has gone offline.
- Implementation:shipped in ethereumclassic/core-geth v1.13.0
- Release:released; every v1.12.x node is asked to upgrade
- Activation:no activation block; the MESS default applies on each node when it upgrades unless switched off
Sources: Core-Geth maintainers (GitHub) — Core-Geth v1.13.0 release notes (external site) · Core-Geth documentation (docs.coregeth.com) — MESS: Modified Exponential Subjective Scoring (external site) · Core-Geth documentation (docs.coregeth.com) — The ETC Cooperative transition (external site) · Core-Geth maintainers (GitHub) — Core-Geth releases (external site) · Core-Geth maintainers (etclabscore, GitHub) — Recent commits to etclabscore/core-geth master (Atom feed) (external site)
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Draft ECIP-1130 proposes the Bastion EVM upgrade
Diego López León and Istora Mandiri opened ECIP-1130, a draft hard fork named Bastion. It would add transient storage opcodes, MCOPY, BLS12-381 and secp256r1 precompiles, a CLZ opcode, bounds and new pricing for MODEXP, and narrower SELFDESTRUCT behaviour. It leaves fees unchanged, defers account-code delegation and a per-transaction gas cap, and sets no activation block.
- Proposal:Draft ECIP
- Implementation:reference implementations still to be linked
- Release:not in any release reviewed here
- Activation:no activation block on Mordor or mainnet
Sources: Ethereum Classic Improvement Proposals — ECIP-1130: Bastion EVM and Protocol Upgrades (external site) · Ethereum Classic Improvement Proposals (GitHub) — ECIPs repository (external site)
-
Two approaches to a base-fee market set out for review
A post co-written by Cody Burns, Diego López León and Istora Mandiri set out two ways to add a base-fee market: the Olympia set (ECIP-1111 to 1119), which would send base fees to an on-chain treasury governed by contracts, with optional miner shares, and ECIP-1120, which would pay base fees to miners, smoothed over past blocks, with no governance layer. The post endorses neither. ECIP-1111 and ECIP-1121 still list no activation block, and OlympiaDAO targets 2027.
- Proposal:Draft ECIPs: the Olympia set from July 2025 to March 2026, ECIP-1120 from December 2025
- Implementation:OlympiaDAO says Fukuii and Core-Geth carry Olympia parameters; the Core-Geth v1.13.0 notes reviewed here do not mention Olympia
- Release:no mainnet release sets an activation block
- Activation:not scheduled; OlympiaDAO targets 2027
Sources: ethereumclassic.org blog (Cody Burns, Diego López León, Istora Mandiri) — The ETC Fee Market Debate: Navigating the Path Forward (external site) · Ethereum Classic Improvement Proposals — ECIP-1111: Base Fee Market and Redirection (external site) · Ethereum Classic Improvement Proposals — ECIP-1120: Basefee Market with Miner Rewards (external site) · Ethereum Classic Improvement Proposals — ECIP-1121: Execution Client Specification Alignment (Olympia Hardfork) (external site) · OlympiaDAO — Upgrade Your Node for Olympia (external site) · Core-Geth maintainers (GitHub) — Core-Geth v1.13.0 release notes (external site)
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Emergency Core-Geth releases after an attack on Ethereum Classic bootnodes
Core-Geth v1.12.21 was an emergency patch for an active attack in which malicious peer traffic made nodes crash-loop through missing checks in the handshake code. v1.12.22 (28 March) moved peer discovery to a new domain and backported further cryptographic fixes, and v1.12.23 (14 August) adopted upstream delayed decoding of peer messages. None of the three changed consensus.
- Implementation:shipped in etclabscore/core-geth v1.12.21 to v1.12.23
- Release:released; strongly recommended for internet-facing nodes
- Activation:no activation block; takes effect when each node upgrades
Sources: Core-Geth maintainers (etclabscore, GitHub) — Core-Geth v1.12.21 (Aegis) release notes (external site) · Core-Geth maintainers (etclabscore, GitHub) — Core-Geth v1.12.22 (Hermes) release notes (external site) · Core-Geth maintainers (etclabscore, GitHub) — Core-Geth v1.12.23 (Argos) release notes (external site) · Core-Geth maintainers (GitHub) — Core-Geth v1.13.0 release notes (external site)
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Besu removes Ethereum Classic support in version 26.2.0
The Besu client, which the community timeline records as supporting Ethereum Classic since 2019, marked Ethereum Classic and Mordor support as deprecated in versions 25.12.0 and 26.1.0 and removed it, including all Ethereum Classic hard-fork settings, in version 26.2.0.
- Implementation:support removed in Besu 26.2.0
- Release:Released
- Activation:applies to anyone who upgrades Besu to 26.2.0 or later
Sources: Besu maintainers (GitHub) — Besu 26.2.0 release notes (external site) · Besu maintainers (GitHub) — Besu CHANGELOG (main branch) (external site) · ethereumclassic.org (community site) — Classic History (roadmap timeline) (external site)
Topics your AI can explain
Your AI can explain these topics for Ethereum Classic through the connection, with sources.
Known gaps
What this profile's review did not establish:
- Total hash rate and mining pool shares were not measured; only one block's difficulty and pool tag were read.
- Node and client counts come from the Core-Geth v1.13.0 release notes citing etcnodes.org; that site did not render for this review.
- How many miners, pools and exchanges run MESS after Core-Geth v1.13.0 is not known, and the ECIP record still shows it switched off.
- Two Core-Geth repositories are active: etclabscore/core-geth (v1.12 line) and ethereumclassic/core-geth (v1.13.0). Which line node operators, pools and exchanges follow, and who runs docs.coregeth.com, were not established.
- Whether Fukuii is ready for mainnet use was not assessed; its latest full release is v0.8.0 (July 2026), later builds are marked pre-release, and how many nodes run it is unknown.
- No activation blocks exist for the Olympia or Bastion proposals, and which approach to base fees will be adopted is open.
- No bridge was confirmed live on Ethereum Classic; DeFiLlama and community listings were not checked against operators' own pages.
- Classic USD's circulating amount and redemption activity were not verified, and whether Ethereum Classic Stable Dollar still operates is unknown.
- Exchange liquidity depth, operator controls and audits of ETCswap, HebeSwap and ETCMC DEX were not reviewed.
- No light client beyond Core-Geth's deprecated light mode was reviewed.
- Atomic swaps, authenticated data publication, reversible transfers or recovery, signed partial offers and payment channels were not researched under their current definitions.
- Full-sync and archive-node resource needs are not measured in Core-Geth's documentation.
- The community site's client page lists only the etclabscore repository, and its endpoint page still lists etc.rivet.link, which Core-Geth's documentation says went offline in August 2026.
- Which derivation path Ledger Wallet and Trezor Suite use for ETC accounts was not checked.
- Blockscout's indexer lagged the chain head by several hundred blocks during this review, so its block-time and gas-price figures are indicative only.
Sources
Oldest dated source check: Source checked Sep 29, 2026 Next check due Oct 29, 2026.
- Ethereum Classic (external site)
- Network: RPC endpoints, explorers and monitors (chain ID 61, ETCHash) (external site)
- Classic History (roadmap timeline) (external site)
- Protocol Upgrades (external site)
- Blockchain Explorers (external site)
- Finance apps (external site)
- ECIP-1000: ECIP Process (external site)
- ECIP-1017: Monetary Policy and Final Modification to the Ethereum Classic Emission Schedule (external site)
- ECIP-1099: Calibrate Epoch Duration (Etchash) (external site)
- ECIP-1100: MESS (Modified Exponential Subjective Scoring) (external site)
- ECIP-1104: Mystique EVM and Protocol Upgrades (external site)
- ECIP-1109: Spiral EVM and Protocol Upgrades (external site)
- ECIP-1110: Deactivate MESS (external site)
- ECIP-1111: Base Fee Market and Redirection (draft) (external site)
- ECIP-1120: Basefee Market with Miner Rewards (draft) (external site)
- ECIP-1130: Bastion EVM and Protocol Upgrades (draft) (external site)
- The ETC Fee Market Debate: Navigating the Path Forward (external site)
- Core-Geth v1.13.0 release notes (external site)
- Core-Geth releases (etclabscore repository, v1.12 line) (external site)
- Recent commits to etclabscore/core-geth master (Atom feed) (external site)
- MESS: Modified Exponential Subjective Scoring (external site)
- The ETC Cooperative transition (external site)
- Hardware requirements (external site)
- Sync modes and data retention (external site)
- Besu 26.2.0 release notes (Ethereum Classic support removed) (external site)
- Fukuii repository and README (external site)
- Fukuii releases (external site)
- ETCswap (external site)
- HebeSwap (external site)
- DeFiLlama protocols API (Ethereum Classic entries) (external site)
- USC (Classic USD) (external site)
- USDC contract addresses (external site)
- Supported protocols (external site)
- Blockscout Ethereum Classic stats API (read 2026-09-29) (external site)
- Ethereum Classic wallet (external site)
- @ledgerhq/cryptoassets 13.56.0 currency list (external site)
- Ledger Wallet EVM network configuration (config.ts, develop branch) (external site)
- Ledger Wallet networks hidden behind feature switches (useCurrenciesUnderFeatureFlag.ts, develop branch) (external site)
- Ethereum Classic explorer (external site)
- Ethereum Classic wallet (external site)
Report an error
Found something wrong or out of date? Reporting is free, and every chain goes through the same process. Published corrections appear in the public log.
Funding disclosure
Funding disclosures appear here when an upkeep arrangement exists, in the form “Upkeep funded by [name]; verdicts unaffected.” The funder ledger has not been published yet. Neutrality & funding