What Is a Wei?
Let me explain what a wei is directly to you: it's the smallest unit of ether, the cryptocurrency on the Ethereum network. One ether equals 1,000,000,000,000,000,000 wei, or 10^18 wei. You can also think of it as one wei being one quintillionth of an ether.
Key Takeaways
A wei relates to ether much like a satoshi does to bitcoin—it's the tiniest unit you can use for transactions. There are various ether units, but gwei stands out because that's how Ethereum gas fees are paid. The wei gets its name from Wei Dai, famous for creating b-money, bitcoin's predecessor, and developing the Crypto++ library.
How a Wei Works
Consider how a U.S. dollar divides into 100 pennies, the smallest unit. Digital currencies go further with even tinier divisions. The wei is that smallest unit for ether on the Ethereum blockchain, named after Wei Dai, a computer engineer and cryptography advocate who pushed for strong privacy tech.
Ether breaks down into subunits of wei, each named to show quantity—like kwei for a thousand wei. They also have nicknames: kwei is a 'babbage,' and gwei is a 'shannon.'
Sub-units of Ether
- Wei: 1 wei = 10^-18 ETH
- Kwei: 10^3 wei = 1,000 = 10^-15 ETH
- Mwei: 10^6 wei = 1,000,000 = 10^-12 ETH
- Gwei: 10^9 wei = 1,000,000,000 = 10^-9 ETH
- Microether: 10^12 wei = 1,000,000,000,000 = 10^-6 ETH
- Milliether: 10^15 wei = 1,000,000,000,000,000 = 10^-3 ETH
- Ether: 10^18 wei = 1,000,000,000,000,000,000 = 1 ETH
The Wei's Exemplar
Wei Dai is known as an intensely private individual, using his cryptography skills to keep his public footprint minimal. From what we know, he graduated from the University of Washington with a computer science degree and worked in Microsoft's cryptography research group.
At Microsoft, Dai focused on studying, designing, and implementing cryptosystems for specialized uses. Before that, he programmed at TerraSciences in Acton, Massachusetts.
As an original cypherpunk from the 1990s, Dai helped lay the groundwork for cryptocurrencies. In his b-money manifesto, he outlined smart contracts that execute automatically without third-party intervention. That's why the atomic unit of ether honors him.
How Much Is 1 Wei of Ether?
One wei is 10^-18 ether. On June 27, 2024, with 1 ETH at $3,456.14, one wei equaled about $0.000000000000003456.
What Is the Difference Between Wei and Gas?
Wei is the base unit of ether. Gas on Ethereum is the fee amount, paid in wei, for processing transactions on the blockchain.
What Is 2.5 Ether to Wei?
To convert ETH to wei, multiply by 10^18. For 2.5 ETH, that's 2,500,000,000,000,000,000 wei.
The Bottom Line
Wei is the smallest unit of ether on Ethereum, equaling one quintillionth of an ether, which makes handling transactions in pure wei cumbersome. That's why other units exist, with gwei (a billion wei) being the go-to for gas charges.
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