Ethereum Unit Converter
All conversions run locally in your browser using native BigInt arithmetic — nothing is sent anywhere, and there's no floating-point precision loss.
How to use this Ethereum unit converter
- Type an amount into any unit field.
- All other units update instantly with exact precision.
- Clear a field to reset all fields to empty.
Why does Ethereum use multiple units?
Wei is the smallest indivisible unit of Ether, similar to how a satoshi relates to Bitcoin — 1 Ether equals 10^18 Wei. Gwei (10^9 Wei) is the standard unit for quoting gas prices, since raw Wei or Ether values would be inconveniently small or large. Szabo (10^12 Wei) and Finney (10^15 Wei) are older intermediate denominations, less common today but still supported by most tooling.
Why use BigInt instead of regular numbers?
JavaScript's regular numbers lose precision above 2^53, and Wei amounts routinely exceed that (1 Ether alone is 10^18 Wei) — BigInt performs exact integer arithmetic with no rounding errors, which matters when every Wei counts.
What's the difference between Gwei and gas price?
Gwei is just a unit of Ether — gas price is a value expressed in that unit, representing how much you pay per unit of gas consumed by a transaction. This converter handles the unit conversion; use OmniDeck's Gas Fee Calculator to estimate a full transaction cost.
Why floating-point math is actually dangerous here, not just imprecise
This isn't an abstract precision concern — floating-point rounding errors in cryptocurrency amounts have caused real financial losses. JavaScript's standard number type can only represent integers exactly up to 2^53 (about 9 quadrillion), and a single Ether is 10^18 Wei, comfortably past that boundary; any calculation involving Wei amounts using regular floating-point numbers risks silently rounding to the wrong value, sometimes by a meaningful amount. BigInt performs exact arbitrary-precision integer arithmetic instead, so a Wei amount converts to Ether and back with zero rounding drift no matter how large the number — this matters enormously here specifically because a rounding error in a financial amount isn't a display quirk, it's a wrong transaction amount.
Wei is what actually exists on-chain — everything else is a display convenience
Every Ethereum smart contract and every node on the network works exclusively in Wei — it's the actual integer unit stored, transmitted, and computed with at the protocol level. Ether, Gwei, Szabo, and Finney don't exist as separate on-chain concepts at all; they're purely human-readable display conventions layered on top of the same underlying Wei integer, each just a different power-of-ten scaling for convenience. This is why wallet software and block explorers convert to Ether or Gwei only for display purposes, while the actual transaction data sent to the network always specifies amounts in raw Wei — understanding this hierarchy explains why this converter exists: translating between the unit humans think in and the unit the blockchain actually uses.
Why gas prices settled on Gwei specifically
Gas prices could technically be expressed in Wei or Ether, but neither is practical for humans to read or type. A typical gas price in raw Wei is a number with 9-10 digits, unwieldy to read at a glance; the same value in Ether is a tiny decimal fraction with many leading zeros, equally hard to parse quickly. Gwei sits in a sweet spot where typical gas prices land in a small, easily readable range (commonly single or low double digits), which is why the ecosystem standardized on quoting gas prices in Gwei specifically, even after Ethereum's EIP-1559 upgrade restructured gas pricing into a base fee plus a priority fee — both components are still conventionally expressed in Gwei for the same readability reason.
The single biggest real-world mistake: an order-of-magnitude error
The most consequential mistake with these units isn't a math error — it's pasting a number into the wrong unit field entirely, treating a Wei amount as if it were Ether, or vice versa. Because each unit differs from its neighbors by many orders of magnitude, an amount that's correct in one unit becomes catastrophically wrong (either negligibly small or absurdly large) if misread as a different unit, and this exact mistake has caused real users to send wildly incorrect transaction amounts by copying a value from one context (say, a raw Wei balance shown by a debugging tool) directly into a field expecting Ether. Double-checking which unit a number actually represents before using it in a real transaction is worth the extra few seconds, precisely because the consequence of getting it wrong here is irreversible.
Limitations of this tool
This tool performs exact unit conversion arithmetic only — it doesn't fetch live gas prices, doesn't estimate what a specific transaction will actually cost (this site's separate Gas Fee Calculator handles that), and doesn't validate that a converted amount makes sense in the context of any specific transaction you're preparing. It also only accepts and displays whole-Wei precision, since Wei is itself the smallest indivisible unit on Ethereum — there's no fractional Wei to represent, so this isn't a limitation in practice, just a reflection of how the underlying unit actually works.