Eth1 / Eth2

What Do Eth1 and Eth2 Mean?

Eth1 and Eth2 are outdated terms that were once used to describe different parts and development stages of Ethereum.

Eth1 generally referred to the original Ethereum Mainnet, including transactions, accounts, smart contracts, the Ethereum Virtual Machine, and the proof-of-work system that originally secured the network.

Eth2, also called Ethereum 2.0, generally referred to a planned collection of upgrades intended to introduce proof-of-stake and improve Ethereum’s scalability, security, and sustainability.

Ethereum developers and educational resources now use the terms execution layer and consensus layer instead.

Eth1 became the execution layer, which handles transactions, smart contract execution, account balances, gas, and blockchain state.

Eth2 became the consensus layer, which handles proof-of-stake validators, attestations, block proposals, fork choice, rewards, penalties, and finality.

The official Ethereum Foundation explanation of the Eth2 renaming states that the preferred relationship is execution layer plus consensus layer equals Ethereum.

There are not two current Ethereum networks called Eth1 and Eth2.

There is one Ethereum network whose execution and consensus layers work together.

Why Are Eth1 and Eth2 Outdated Terms?

The terms became outdated because they suggested that Ethereum would abandon one network and replace it with a completely separate network.

Earlier versions of the Ethereum roadmap envisioned the original proof-of-work chain being replaced or migrated into a new proof-of-stake system.

This made names such as Ethereum 1.0 and Ethereum 2.0 seem reasonable at the time.

The technical roadmap later changed.

Instead of moving every account, smart contract, and application to a replacement chain, developers preserved Ethereum’s existing execution history and connected it to the new proof-of-stake consensus system.

The result was a layered architecture rather than a simple replacement from version one to version two.

Using Eth1 and Eth2 after this change created confusion about whether two coins, networks, or versions of Ethereum existed.

The terminology was therefore phased out in favor of names that describe the actual responsibilities of each layer.

What Replaced the Term Eth1?

The term Eth1 was replaced by execution layer.

The execution layer processes transactions and maintains Ethereum’s application-facing state.

It includes externally owned accounts, contract accounts, ETH balances, smart contract bytecode, contract storage, transaction receipts, and event logs.

It also includes the Ethereum Virtual Machine, which executes smart contract instructions.

Execution clients validate transaction signatures, account nonces, gas limits, contract calls, and the resulting state transitions.

Wallets and decentralized applications commonly communicate with the execution layer through Ethereum JSON-RPC methods.

The execution layer is not a separate blockchain that users must join independently.

It is one essential part of the unified Ethereum protocol.

What Replaced the Term Eth2?

The term Eth2 was replaced by consensus layer.

The consensus layer coordinates Ethereum’s proof-of-stake validators and determines which valid chain history the network accepts.

It manages validator activation, attestations, block proposals, rewards, penalties, slashing, fork choice, justification, and finality.

The consensus layer began with the Beacon Chain, which launched separately from Ethereum Mainnet on December 1, 2020.

The Beacon Chain initially tracked validators and proof-of-stake consensus without processing ordinary Ethereum Mainnet transactions.

After The Merge, it became Ethereum’s consensus engine for blocks containing execution-layer transactions.

The official Ethereum Beacon Chain documentation explains that the Beacon Chain is now the consensus layer rather than a separate future Ethereum network.

Execution Layer Plus Consensus Layer

The execution layer and consensus layer perform different tasks but depend on each other.

The execution layer determines whether transactions and smart contract state changes are valid.

The consensus layer determines how valid blocks are proposed, ordered, confirmed, and finalized.

A proposed Ethereum block contains a consensus-layer structure and an execution payload.

The execution client checks the transactions inside the execution payload.

The consensus client checks validator signatures, block timing, attestations, fork-choice rules, and other proof-of-stake requirements.

A block must satisfy both layers’ rules to become part of the accepted Ethereum chain.

Neither layer should be described as the old or new Ethereum because both are required for the current network.

What Was Ethereum 2.0?

Ethereum 2.0 was an umbrella term for a changing research and development roadmap.

It included proof-of-stake, the Beacon Chain, validator economics, sharding concepts, and other changes intended to improve Ethereum.

Researchers began combining several upgrade efforts under the Ethereum 2.0 name around 2018.

Early plans divided development into numbered phases such as Phase 0, Phase 1, and Phase 2.

Phase 0 generally referred to launching the Beacon Chain and proof-of-stake validator system.

Later phases were expected to introduce shard chains and additional execution capabilities.

The roadmap changed as rollups developed and as engineers found a safer way to connect the Beacon Chain with the existing Mainnet execution environment.

Because the original phased roadmap was no longer an accurate description of Ethereum’s development, the Ethereum 2.0 label became misleading.

Was Eth2 a New Blockchain?

The Beacon Chain initially existed as a separate proof-of-stake blockchain running beside the original proof-of-work Mainnet.

It did not initially process ordinary Ethereum transactions, decentralized applications, or smart contract calls.

Its early purpose was to operate and test the proof-of-stake validator system.

The broader Eth2 concept was often described as a future Ethereum environment, which led some users to believe that every application and asset would move to a replacement blockchain.

That full replacement did not occur.

The Merge connected the Beacon Chain’s consensus system to Ethereum Mainnet’s existing execution state.

After that connection, there were no longer two separate Ethereum chains serving those roles.

The network became one proof-of-stake Ethereum with an execution layer and a consensus layer.

What Was The Merge?

The Merge was the upgrade that replaced Ethereum Mainnet’s proof-of-work consensus with proof-of-stake.

It was completed on September 15, 2022.

The original Mainnet execution layer joined with the Beacon Chain consensus layer.

The execution layer preserved Ethereum’s existing accounts, balances, smart contracts, applications, and transaction history.

The consensus layer replaced miners with validators as the participants responsible for block production and confirmation.

The official Ethereum documentation about The Merge explains that proof-of-work was permanently replaced while the existing blockchain history remained intact.

The Merge did not create a new ETH asset.

It changed the system used to reach consensus about Ethereum’s existing state.

Did Eth1 Become Eth2?

Eth1 did not simply transform into Eth2 in the way software may upgrade from version one to version two.

The original execution environment continued operating while its proof-of-work consensus responsibilities were removed.

The Beacon Chain’s proof-of-stake system became the consensus layer for that execution environment.

Both components now form the same Ethereum network.

It is more accurate to say that the original execution layer and the Beacon Chain consensus layer were combined through The Merge.

Describing current Ethereum as Eth2 ignores the continuing role of the original Mainnet execution history.

Did The Merge Erase Eth1 History?

The Merge did not erase Ethereum’s earlier transaction history.

Every Mainnet account, smart contract, token balance, and historical block remained part of Ethereum after the transition.

A contract deployed before The Merge continued to exist at the same address unless its own code or administrator changed it.

A user’s ETH balance did not need to be transferred to another network.

The consensus mechanism changed, but the execution state continued.

This continuity is one of the main reasons why the Eth1 and Eth2 version labels are inaccurate.

Was There an ETH1 Coin or ETH2 Coin?

There was no official ETH1 coin and no official ETH2 coin that users needed to exchange.

ETH remained the native cryptocurrency of Ethereum before and after The Merge.

The official Merge guidance states that there is no old ETH, new ETH, ETH1, or ETH2 asset.

A person claiming that users must convert ETH into ETH2 may be attempting fraud.

No wallet migration, token swap, private-key submission, or recovery-phrase entry was required because of the naming change or The Merge.

Tokens using names such as ETH2 may represent unrelated products, accounting balances, or privately issued claims rather than a protocol-level Ethereum asset.

Users should identify the issuer and contract before interacting with any token that uses Ethereum upgrade terminology.

Did Users Need to Upgrade Their ETH?

Ordinary ETH holders did not need to perform any action for The Merge.

Private keys and wallet addresses continued working with the same Ethereum accounts.

Assets remained at their existing addresses.

Smart contracts continued using the existing Ethereum state.

A website requesting a recovery phrase to upgrade ETH should be treated as malicious.

Protocol upgrades are adopted by node software and do not require ordinary users to send assets to a conversion address.

Did The Merge Lower Ethereum Gas Fees?

The Merge did not directly lower Ethereum gas fees.

It changed the consensus mechanism rather than significantly expanding execution capacity.

Gas fees depend mainly on demand for block space, available capacity, transaction complexity, and fee-market rules.

The official Merge documentation states that reducing gas fees was not an intended direct result of the transition to proof-of-stake.

Later scaling work has focused heavily on Layer 2 networks and lower-cost data availability for rollups.

Users should not treat Eth2 as the name of an upgrade that permanently made all Ethereum transactions inexpensive.

Did The Merge Make Ethereum Transactions Faster?

The Merge did not create a dramatic increase in Ethereum Mainnet transaction throughput.

Proof-of-stake introduced approximately 12-second slots and changed block-production timing.

However, it did not multiply the number of ordinary transactions that could fit into every block.

Users may have observed slightly more predictable block timing, but this was not the same as a major scaling expansion.

Ethereum’s broader scaling strategy relies strongly on rollups, data availability improvements, and continuing protocol upgrades.

Did Eth2 Enable Staking?

The work historically called Eth2 introduced Ethereum’s proof-of-stake validator system.

The Beacon Chain began accepting validator deposits and operating proof-of-stake consensus in December 2020.

Before The Merge, Beacon Chain validators confirmed the Beacon Chain’s own state rather than Mainnet execution transactions.

After The Merge, validators became responsible for securing the unified Ethereum network.

A native validator requires at least 32 ETH to activate under current protocol rules.

Staking rewards compensate validators for correct participation, while downtime and conflicting signatures can create penalties.

Staking is now simply called Ethereum staking rather than Eth2 staking.

Did The Merge Enable Staking Withdrawals?

The Merge did not immediately enable withdrawals of staked ETH.

Validator withdrawals were activated later through the Shanghai and Capella upgrades on April 12, 2023.

The combined upgrade is commonly called Shapella.

Shapella enabled partial withdrawals of eligible rewards and full withdrawals after validator exits.

This separate activation shows why Ethereum 2.0 was not one single upgrade with every expected feature delivered at once.

The current Ethereum staking withdrawal documentation explains the available withdrawal processes.

What Happened to Ethereum Mining?

Ethereum mining ended when The Merge replaced proof-of-work with proof-of-stake.

Miners no longer produce valid Ethereum Mainnet blocks.

Validators now propose blocks and submit attestations.

Mining equipment cannot generate new native ETH through the current Ethereum protocol.

A service claiming to mine new Ethereum Mainnet ETH after September 15, 2022 should be treated with caution.

Mining may still exist on separate proof-of-work blockchains, but those networks are not Ethereum Mainnet.

How Ethereum Nodes Changed After The Merge

Before The Merge, an Ethereum Mainnet node could use an execution client to validate transactions and follow proof-of-work consensus.

After The Merge, a full node requires both an execution client and a consensus client.

The execution client processes transactions and maintains Ethereum state.

The consensus client follows validators, proof-of-stake blocks, fork choice, and finality.

The two clients communicate through the Engine API.

The official Ethereum node architecture documentation explains that current nodes use these coordinated client layers.

A validator node also uses validator software to sign its assigned duties.

Running an ordinary non-validating node does not require staking ETH.

What Is the Engine API?

The Engine API is the interface through which an Ethereum execution client and consensus client coordinate.

The consensus client can ask the execution client to prepare or validate an execution payload.

The execution client can report whether the payload’s transactions and state transition are valid.

The consensus client combines this execution result with proof-of-stake consensus information.

The connection is normally authenticated with a shared JSON Web Token secret.

The Engine API helps preserve a separation of responsibilities while allowing the two layers to operate as one node.

Execution Clients and Consensus Clients

Execution clients implement Ethereum’s transaction and smart contract rules.

They maintain the EVM, transaction pool, execution state, receipts, logs, and execution-layer peer network.

Consensus clients implement proof-of-stake rules.

They follow slots, epochs, validator attestations, block proposals, fork choice, justification, and finality.

Different client implementations can be written in different programming languages.

Compatible clients must follow the same active Ethereum protocol specifications and produce the same valid results.

Client diversity helps reduce Ethereum’s dependence on one software implementation.

Why Was the Terminology Changed Before The Merge?

Ethereum’s core developers began moving away from Eth1 and Eth2 terminology before The Merge occurred.

By late 2021, execution layer and consensus layer had become the preferred technical descriptions.

The change reduced the false impression that the original Ethereum network was being discarded.

It also prevented users from thinking that Eth2 was a separate investment asset.

The new terminology reflects how current Ethereum software is organized.

The naming change did not alter balances, protocol goals, or the upgrade roadmap by itself.

Why “Ethereum 2.0” Can Be Misleading

The label Ethereum 2.0 suggests one final software release that permanently completes Ethereum development.

Ethereum is instead upgraded through a continuing series of coordinated protocol changes.

Some earlier Eth2 ideas were implemented, some were reorganized, and others were replaced by different approaches.

Proof-of-stake and the Beacon Chain became central parts of Ethereum.

The original plan for execution across many shard chains changed as rollups became the main method for scaling transaction execution.

Later upgrades introduced withdrawals, blob transactions, validator improvements, data availability changes, and other features outside the original numbered phase structure.

The current Ethereum roadmap presents these developments as continuing Ethereum upgrades rather than releases of a separate Ethereum 2.0 network.

What Happened to Shard Chains?

Early Ethereum 2.0 roadmaps expected shard chains to divide transaction processing across several protocol-managed chains.

The rise of Layer 2 rollups changed the priority and purpose of Ethereum sharding research.

Rollups process transactions separately and use Ethereum for settlement and data availability.

Ethereum therefore shifted toward improving the availability of low-cost data for rollups rather than placing ordinary smart contract execution on traditional shard chains.

Proto-danksharding introduced temporary blob data through the Dencun upgrade in March 2024.

Later upgrades continued increasing and improving Ethereum’s capacity to support rollup data.

This change is another reason why an old Eth2 phase diagram should not be treated as the current roadmap.

Eth1, Eth1.x, and Execution-Layer Research

Eth1.x was an older name used for research intended to improve the original Ethereum proof-of-work chain before or alongside the broader Ethereum 2.0 roadmap.

Research areas included state growth, client efficiency, statelessness, data structures, and execution improvements.

When the naming system changed, Eth1.x work was generally described as execution-layer research.

Some concepts developed under the older label continued to influence Ethereum even after the terminology changed.

An archived document using Eth1.x is not necessarily incorrect, but readers should interpret it in its historical context.

Eth2 and the Beacon Chain

Eth2 and Beacon Chain were sometimes used as though they meant the same thing, but they were not exact synonyms.

Ethereum 2.0 referred to a broad collection of proposed upgrades.

The Beacon Chain was a specific proof-of-stake blockchain launched as part of that effort.

It maintained a validator registry, validator balances, consensus votes, rewards, and penalties.

After The Merge, the Beacon Chain became Ethereum’s consensus layer.

The name Beacon Chain may still appear in technical descriptions, APIs, block roots, or historical material.

Its presence does not imply that a separate Eth2 network still exists.

Eth1 / Eth2 and Smart Contracts

Smart contracts remained on Ethereum’s execution layer through The Merge.

Developers did not need to redeploy every contract onto an Eth2 chain.

Contract addresses, storage, token balances, and transaction history remained part of the same Mainnet state.

The Merge did create some application-level changes involving block timing, block fields, finality concepts, and sources of on-chain randomness.

Developers relying on low-level block behavior needed to review those differences.

For most ordinary application users, the transition required no manual contract or token migration.

Eth1 / Eth2 and Wallets

A wallet does not need separate Eth1 and Eth2 accounts for ordinary Ethereum use.

The same Ethereum address can receive ETH and interact with Mainnet smart contracts.

A validator has specialized signing keys and withdrawal credentials, but those do not create a second general-purpose ETH currency.

Some older wallet interfaces or services used Eth2 labels for balances connected with staking products.

Such a label may describe an internal claim, locked balance, or staking representation rather than native Ethereum protocol terminology.

Users should review the exact product terms instead of assuming that a displayed Eth2 balance is a separate official coin.

Eth1 / Eth2 and Crypto Trading

Crypto traders may still encounter ETH2 terminology in historical articles, old market commentary, staking products, or token names.

The term should not be interpreted as the ticker for an upgraded form of native ETH.

Native ETH remained ETH through The Merge.

A separate token using an Eth2-related name can carry issuer, smart contract, redemption, liquidity, and counterparty risks.

Its market price may differ from ETH even when it is intended to represent a claim on staked ETH.

Traders should verify the contract, issuer, redemption process, and underlying assets before acquiring such a token.

Eth1 / Eth2 Scam Risks

The outdated terminology has been used in scams that tell users they must upgrade ETH before a deadline.

A scammer may request that ETH be sent to a conversion address in exchange for supposed ETH2 tokens.

Another scam may request a private key or recovery phrase to synchronize a wallet with the proof-of-stake network.

These actions were never required by The Merge.

A legitimate protocol upgrade does not require users to disclose wallet recovery information.

Users should also reject claims that old ETH became invalid after September 2022.

ETH balances continued automatically on the unified Ethereum network.

How to Read Old Eth1 and Eth2 Documentation

Older documentation can still provide useful historical and technical context.

The first step is to check the publication date.

The second step is to determine whether Eth1 refers to the original execution chain, proof-of-work consensus, or older execution-layer research.

The third step is to determine whether Eth2 refers to the Beacon Chain, proof-of-stake, staking, sharding, or the entire former upgrade roadmap.

The fourth step is to check whether the described feature was implemented, changed, delayed, or replaced.

The fifth step is to compare the claim with current Ethereum documentation and protocol specifications.

Terms such as Phase 0, Phase 1, Phase 2, Serenity, shard chains, Eth1.x, and Ethereum 2.0 should usually be interpreted as historical roadmap language.

Correct Terminology to Use Today

Use Ethereum when referring to the full unified network.

Use execution layer when referring to transactions, the EVM, smart contracts, gas, accounts, and execution state.

Use consensus layer when referring to proof-of-stake validators, attestations, block proposals, fork choice, and finality.

Use Ethereum staking when referring to validator participation rather than Eth2 staking.

Use Ethereum upgrades or the Ethereum roadmap when discussing continuing protocol development.

Use Beacon Chain when the historical or technical context specifically requires that name.

These terms describe Ethereum more accurately and reduce the risk of confusion about separate coins or networks.

Common Misunderstandings About Eth1 and Eth2

One common misunderstanding is that Eth2 replaced every part of Eth1.

The original execution state continued and was connected to proof-of-stake consensus.

Another misunderstanding is that ETH had to be converted into ETH2.

No official conversion was required or offered.

A third misunderstanding is that Ethereum currently operates two Mainnets.

There is one Ethereum Mainnet with execution and consensus layers.

A fourth misunderstanding is that The Merge immediately lowered gas fees.

The Merge changed consensus rather than significantly expanding block capacity.

A fifth misunderstanding is that The Merge enabled every Ethereum 2.0 feature at once.

Staking withdrawals and later scaling improvements were delivered through separate upgrades.

A sixth misunderstanding is that an old Eth2 roadmap remains Ethereum’s current development plan.

The roadmap evolved toward rollup-focused scaling and ongoing named upgrades.

FAQ

What does Eth1 mean?

Eth1 is an outdated term for Ethereum’s original Mainnet and is now generally called the execution layer.

What does Eth2 mean?

Eth2 is an outdated term associated with Ethereum’s proof-of-stake and scaling roadmap and is now generally replaced by consensus layer or Ethereum upgrades.

Are Eth1 and Eth2 separate blockchains today?

No, the execution and consensus systems operate together as one Ethereum network.

Is Ethereum 2.0 still the official name?

No, Ethereum documentation has phased out Ethereum 2.0 in favor of more precise terms such as execution layer, consensus layer, and Ethereum roadmap.

Is there an ETH2 cryptocurrency?

No, Ethereum did not create an official ETH2 coin that holders needed to receive or purchase.

Did ETH become ETH2 after The Merge?

No, native ETH remained the same Ethereum asset before and after The Merge.

Did users need to convert their ETH?

No, wallets, balances, contracts, and transaction history continued automatically without a token conversion.

What replaced Eth1?

The execution layer replaced the Eth1 label and handles transactions, accounts, smart contracts, gas, and Ethereum state.

What replaced Eth2?

The consensus layer replaced the Eth2 label for proof-of-stake consensus, although the former Eth2 roadmap included additional scaling ideas.

What was The Merge?

The Merge was the September 15, 2022 upgrade that connected Ethereum’s original execution layer with the Beacon Chain consensus layer and ended proof-of-work mining.

Was any Ethereum history lost during The Merge?

No, Ethereum’s accounts, balances, contracts, and transaction history remained intact.

Did The Merge reduce gas fees?

No, it changed Ethereum’s consensus mechanism and was not designed as a major increase in transaction capacity.

Did The Merge enable staking withdrawals?

No, staking withdrawals were enabled later through the Shanghai and Capella upgrades on April 12, 2023.

Can ETH still be mined?

No, Ethereum Mainnet now uses proof-of-stake validators and no longer accepts proof-of-work mining.

Does running an Ethereum node require 32 ETH?

No, anyone can run a non-validating node without staking ETH, while validator activation requires the protocol’s minimum effective balance.

Why does a current Ethereum node need two clients?

It needs an execution client to process transactions and a consensus client to follow proof-of-stake blocks and finality.

Is the Beacon Chain still separate from Mainnet?

No, it became Ethereum’s consensus layer through The Merge.

What happened to the original Eth2 shard-chain plan?

Ethereum shifted toward rollup-based execution and data availability improvements rather than the earlier plan for execution across traditional shard chains.

Can a token labeled ETH2 be different from ETH?

Yes, a privately issued token using that name may represent a separate staking claim or product and can have additional issuer, contract, and liquidity risks.

What terminology should developers use now?

Developers should normally use Ethereum, execution layer, consensus layer, Beacon Chain when specifically relevant, and the names of individual protocol upgrades.

Conclusion

Eth1 and Eth2 are historical terms that no longer accurately describe Ethereum’s architecture.

Eth1 generally referred to the original Ethereum Mainnet and is now called the execution layer.

Eth2 generally referred to the proof-of-stake and scaling roadmap and is now represented more accurately by the consensus layer and Ethereum’s continuing roadmap.

The execution layer processes transactions, smart contracts, gas, accounts, and blockchain state.

The consensus layer manages validators, attestations, block proposals, rewards, penalties, fork choice, and finality.

The Merge joined these systems on September 15, 2022 and permanently ended Ethereum proof-of-work mining.

The Merge preserved Ethereum’s existing balances, smart contracts, applications, and transaction history.

It did not create a new ETH2 coin, require a token conversion, immediately lower gas fees, or enable staking withdrawals.

Later upgrades delivered withdrawals, rollup data improvements, validator changes, and other developments as part of one continuously evolving Ethereum network.

Current users should say Ethereum rather than Eth2 and should use execution layer or consensus layer when discussing a specific part of the protocol.

Understanding the change from Eth1 and Eth2 terminology helps crypto users interpret older documentation, recognize conversion scams, and understand why present-day Ethereum is one network supported by two coordinated protocol layers.