What is the flippening in crypto?

The flippening is the name crypto users give to a possible future in which Ethereum's market capitalization overtakes Bitcoin's. It does not mean one ether costing more than one bitcoin. It means the combined value of all ether in circulation exceeding the combined value of all bitcoin. Supporters of Ethereum have discussed it for years, and it remains a hypothetical event.

What is the flippening in crypto?

Coinbase, Ledger and CoinMarketCap all trace the term to 2017. That year, interest in Ethereum's smart contracts and the apps built on them pushed ether up sharply against bitcoin. CoinMarketCap notes the term was coined when Ethereum hit its all-time high against Bitcoin, and that Ethereum's share later fell back.

The comparison rests on market cap, which multiplies price by circulating supply. For a background on how the two networks differ in purpose and design, see Bitcoin vs Ethereum.

Has the flippening happened?

Not by market cap. As of November 2026, CoinGecko's market cap ranking lists bitcoin first and ether second, with bitcoin's value several times larger.

On other measures, Ethereum has already pulled ahead. CoinMarketCap says Ethereum has passed Bitcoin in transaction count and in total transaction fees, while Bitcoin still leads on trading volume, search interest, active addresses and market cap. Coinbase and Ledger add that Ethereum briefly led in transaction volume during 2021. These partial flips are sometimes called flippenings too, but the original term is about total value.

Ledger notes that the event is not guaranteed. Bitcoin's supply is capped while ether's is not, which our guide on whether Ethereum has a max supply explains.

How does the flippening work with Ethereum and Bitcoin market cap?

Because market cap is price times supply, the flippening can come from either side. Ledger and Coinbase both point out that ether could rise faster than bitcoin, bitcoin could fall further than ether, or some mix of the two could happen. CoinMarketCap estimated in 2022 that Ethereum would need an ETH/BTC price ratio of roughly 0.17 or more, though that figure shifts as each coin's supply changes.

A related measure is bitcoin dominance, bitcoin's share of the whole crypto market. It looks at bitcoin against everything else, while the flippening is a head-to-head comparison with one rival.

What is the flippening index?

The Flippening Index is a composite score that compares Ethereum with Bitcoin across several metrics at once. Cointelegraph reported in July 2020 that Holger Rohm of The Blockchain Center, a German site, built it from eight indicators. Named examples included transaction count, fees, dollar transaction volume, active addresses, exchange trading volume, Google searches and node count, weighted equally. It drew mainly on data from CoinGecko and Coin Metrics.

At the time, the index read 53.3%, while ether's market cap was only 14.9% of bitcoin's. That gap shows why the index and the market-cap race are different questions. A high index reading says Ethereum is busy, not that its value has caught up.