Gwei, is a small denomination of the cryptocurrency Ether (ETH), the native currency of the Ethereum blockchain. Gwei is short for gigawei and is also called a nanoether, or simply nano, to denote the ninth power of the fractional ETH. Along with ETH, gwei is the most commonly used denomination of Ethereum’s cryptocurrency, and it is notably useful when talking about gas, and the Ethereum network's transaction fees.^[1][5]

The breakdown of ether to wei is as follows:

1 ether = 1,000,000,000 gwei

1 gwei = 1,000,000,000 wei

Therefore 1 ether = 1,000,000,000,000,000,000 Wei

Uses

Gwei is the most commonly used unit of ether because "gas" prices are easily specified in gwei. For instance, instead of saying that gas for a transaction costs 0.000000001 ether, one can say it costs 1 gwei. Gas, referring to the Ethereum network's transaction fees, in gwei are payments made by users to compensate for the computing energy required to process and validate transactions on the blockchain. ^[2]

Denominations of Ether

Wei (Wei) -  Dai Wei who formulated the concepts of all modern cryptocurrencies, and is best known as the creator of the predecessor to Bitcoin, B-money.

Kwei (Babbage) -  Charles Babbage (1791-1871) was an English mathematician and mechanical engineer who is considered the father of the computer. Babbage’s designs for his analytical engine, a mechanic computer, would go on to inspire modern computer scientists. Modern recreations of his designs have been successful in proving his idea would have worked if it was feasible to build.

Mwei (lovelace) -  Ada Lovelace (1815-1852), a brilliant mathematician and daughter of the poet Lord Byron, collaborated with Babbage. She wrote what many consider the first computer program which would have derived Bernoulli numbers had the engine ever been built. She also had the idea of applying punchcards from weaving looms to input a sequence of instructions into Babbage’s analytical engine.

Gwei (Shannon) -  Claude Shannon (1916-2001) was an American mathematician and electrical engineer known as “the father of information theory.” Shannon also designed early digital circuits which could solve Boolean algebra. His work laid the groundwork for the digital computers and networks we use today.

Twei (Szabo) -  Nick Szabo, is a computer scientist, legal scholar, and cryptographer known for his pioneering research in digital contracts and digital currency. Szabo designed bit gold, a decentralized digital currency also said to have influenced Satoshi Nakamoto’s design of Bitcoin. Szabo proposed and coined the term “smart contracts.

Pwei (Finney) - for Hal Finney (1956-2014) was a cryptographic activist, developer for the PGP Corporation, creator of reusable proof of work, and early Bitcoin contributor. Finney was allegedly the first recipient of a Bitcoin transaction, sent from Satoshi Nakamoto himself.

Ether (buterin) - for Vitalik Buterin, creator of Ethereum.^[3][4]