The smallest unit of ether is denoted as wei. The conversion table for ether and wei is as follows:
| Unit | Wei value | Wei | Ether value | Ether |
| Wei | 1 wei | 1 | 10-18 ether | 0.000000000000000001 |
| Kwei (KiloWei/babbage) | 103 wei | 1,000 | 10-15 ether | 0.000000000000001 |
| Mwei (MegaWei/lovelace) | 106 wei | 1,000,000 | 10-12 ether | 0.000000000001 |
| Gwei (GigaWei/shannon) | 109 wei | 1,000,000,000 | 10-9 ether | 0.000000001 |
| microether (szabo) | 1012 wei | 1,000,000,000,000 | 10-6 ether | 0.000001 |
| milliether (finney) | 1015 wei | 1,000,000,000,000,000 | 10-3 ether | 0.001 |
| ether | 1018 wei | 1,000,000,000,000,000,000 | 1 ether | 1 |
The most commonly used terms are ether, gwei, and wei. These units are used in many places in the Ethereum ecosystem, such as when creating a new transaction, or when setting the gas price for a transaction. These units can also be used in the Solidity language, hence Solidity supports wei, finney, szabo, and ether units.