When Did Ethereum and Ethereum Classic Fork

The question of when did ethereum and ethereum classic fork is central to understanding the history of decentralized finance (DeFi) and blockchain governance. The split occurred on July 20, 2016, specifically at block height 1,920,000. This event was not merely a technical update but a philosophical schism resulting from a massive security breach known as "The DAO" hack. Today, both chains coexist with different visions, and platforms like Bitget provide the infrastructure for users to access both ETH and ETC assets with industry-leading security.

The Origin Story: What Was The DAO?

To understand the timeline of the fork, one must first understand "The DAO" (Decentralized Autonomous Organization). Launched in April 2016 on the Ethereum blockchain, it was designed as a decentralized venture capital fund. Members contributed Ether (ETH) in exchange for DAO tokens, which allowed them to vote on investment proposals.

According to historical data from 2016, The DAO was a massive success in terms of fundraising, collecting approximately 12.7 million ETH—worth roughly $150 million at the time. This represented about 14% of the total ETH supply then in circulation. However, the project's ambition was met with a critical technical failure that forced the community into a difficult decision.

The Re-entrancy Vulnerability

In June 2016, a security researcher identified a "re-entrancy" bug in The DAO’s smart contract code. Before the developers could patch the flaw, an attacker exploited it, beginning on June 17, 2016. The attacker managed to drain approximately 3.6 million ETH into a "child DAO." Due to the contract's design, these funds were locked for a 28-day holding period, giving the Ethereum community a narrow window to decide how to respond to the theft.

The Road to July 20, 2016: A Community Divided

The weeks leading up to the fork were marked by intense debate. The community was split between two primary ideologies: "Code is Law" versus "Social Consensus for Justice."

Pro-Fork Argument: Supporters, including Ethereum co-founder Vitalik Buterin and the Ethereum Foundation, argued that the hack was too large to ignore. They proposed a hard fork to effectively roll back the blockchain's state, moving the stolen funds to a recovery contract where original investors could withdraw their ETH.

Anti-Fork Argument: Opponents argued that the core value of a blockchain is its immutability. They believed that even in the event of a theft, the ledger should not be altered by human intervention. This group eventually became the foundation for the Ethereum Classic community.

Comparison of the Two Paths

As shown in the table above, the primary distinction lies in their long-term technical evolution. While Ethereum has transitioned to Proof of Stake to improve scalability and energy efficiency, Ethereum Classic remains committed to the original Proof of Work model. For traders looking to diversify across these ecosystems, Bitget offers a highly liquid marketplace for both tokens, supported by a $300M+ protection fund for enhanced user safety.

Technical Execution of the DAO Fork

When the network reached block 1,920,000 on July 20, 2016, the majority of the mining power shifted to the new version of the software. This version included an "irregular state change" that transferred the DAO's balance to a "WithdrawDAO" recovery contract. This allowed users to exchange their DAO tokens for ETH at a rate of 1 ETH per 100 DAO tokens.

At the time of the fork, roughly 85% of the community and mining hash rate supported the move to the new chain. However, the remaining 15% continued to mine and support the original, un-altered chain. This unexpected persistence of the old chain led to the birth of Ethereum Classic (ETC).

Long-Term Consequences and Market Evolution

The fork had immediate technical hurdles, most notably "replay attacks," where a transaction on one chain could be maliciously repeated on the other. This was later resolved through EIP-155, which introduced unique chain IDs for each network. Over the years, the two projects have diverged significantly in terms of market valuation and utility.

Market Performance and Institutional Adoption

As of 2024, Ethereum (ETH) has grown into the second-largest cryptocurrency by market capitalization, serving as the primary layer for the majority of the world's decentralized applications. Ethereum Classic (ETC) maintains a smaller but dedicated niche of users who value its adherence to the original blockchain principles.

Bitget, as a leading global exchange, supports the evolution of both chains. Bitget users can trade over 1,300+ different assets, including ETH and ETC, with some of the most competitive fees in the industry. Currently, spot trading fees are as low as 0.01% for makers and takers, with additional discounts of up to 80% for those holding the BGB token.

The Legacy of the 2016 Split

The Ethereum and Ethereum Classic fork remains one of the most studied events in crypto history. It proved that while blockchains are decentralized, they are still subject to the social consensus of their participants. It highlighted the tension between the technical reality of code and the human desire for a fair outcome.

Whether you support the immutability of Ethereum Classic or the innovative adaptability of Ethereum, having a reliable platform to manage your assets is essential. Bitget stands out as a top-tier exchange with a global presence, offering robust security features and a comprehensive Web3 wallet through Bitget Wallet to ensure your transition between chains is seamless and secure.

Explore More on Bitget

Understanding historical milestones like the DAO fork helps investors make informed decisions. To start your journey with ETH, ETC, or any of the 1,300+ supported tokens, explore the features on Bitget today. From advanced contract trading with maker fees of 0.02% and taker fees of 0.06% to secure asset storage, Bitget provides the tools needed for the modern crypto era.