Ethereum and Ethereum Classic

What’s the difference?

There’s a lot of newcomers to this space so I want to lay out what I believe are some key differences between Ethereum and Ethereum Classic. I’ve attempted to be as unbiased as possible. You are welcome to discuss and seek out other opinions, no one is the final authority on anything.

Disclaimer: I own both currencies. Classic is my favorite of the two.

On Blockchain Mutability

  • Ethereum — Blockchain records and contracts should be revised if a majority agrees to revise the chain (ie. mutability).
  • Classic — Blockchain records and contracts should never be changed (ie. immutability).

There are pros and cons to each approach.

On the side of mutability is the idea that crowds have enough wisdom to make the right decision. It is therefore pragmatic to reverse thefts rather than pursue thieves.

On the side of immutability is the opposite, that crowds, regardless of wisdom, may not always make the correct decision. It is therefore better to pursue thieves through existing legal frameworks.

On Development

  • Ethereum — Whether by design or nature core blockchain decisions are made and largely developed by The Ethereum Foundation with community input.
  • Classic — Blockchain decisions are largely made through feedback from three loosely coordinated teams with community input.

In either case anyone can submit Improvement Proposals for either or both blockchains. This is the beauty of open source and a very common occurrence. You’ll find that developers of both chains communicate with each other over Github and Reddit. I expect this to increase as they work towards common goals.

On Compatibility

Both Blockchains are currently compatible with each other. Contracts (applications) written on one can operate on the other.

  • Ethereum — Focused on eWASM to open their platform to as many developers as possible. More secure contracts are secondary (ex. Viper).
  • Classic — Focused on giving developers the ability to create more secure contracts (ex. Viper, IOHK’s research) at the cost of total potential developer count.

Obviously both chains can adopt each other’s changes. Whether or not they will is a different matter. It’s my own opinion that number of developers does not necessarily equate to the quality of the product.

On Transaction Speed

  • Ethereum —25 second block times on average. This is likely to be decreased in an upcoming upgrade bringing block times back down (Metropolis).
  • Classic — 14 seconds on average. Likely to stay between 10–14 seconds in upcoming upgrades (ECIP-1010 and ECIP-1036).

Update: Ethereum fixed their block time issues. We’re now about the same average block time.

On Block Capacity

  • Ethereum — Blocks are getting full as Ethereum reaches nearly 500k transactions per day, this could result in the same transaction fee issues recently seen in Bitcoin. This should be addressed in Metropolis to allow for larger blocks (by increasing the default gas limit).
  • Classic — Blocks currently have lots of space. As with Ethereum this will change with increasing adoption of Classic.

On Community

  • Ethereum — Most discussion happens on Reddit.
  • Classic — Most discussion happens on Discord.

On Monetary Policy

  • Ethereum — Plans to have a steadily increasing supply resulting in ~3% inflation on average for the lifetime of the Ethereum Blockchain.
  • Classic — Plans to have ~3% inflation until ~2025, at which point total supply will be ~200 million ETC. Afterwards it will be deflationary.

On Trade Volume by Locality

  • Ethereum — 20% in China, 25% in South Korea, 25% in USA.
  • Classic — 50% in China, 25% in South Korea, 10% in USA.

On Securities

  • Ethereum — Does not currently have any options for investors to trade securities. An Ethereum ETF was very recently denied.
  • Classic — Has the Ethereum Classic Investment Trust which allows investors to own ETC without holding the asset themselves.

Data is from’s trading volume in the past 24 hours. USA includes USD and USDT pairs.