Wei, Gwei and BNB: Crypto Units Explained
Home › Guides · By BscScan.Support Editorial · 3 min read · Updated July 2026
Open any raw blockchain data and you'll see absurd numbers: a balance of 1500000000000000000, a gas price of 50000000. These aren't bugs — the chain doesn't use decimals at all. It counts in whole units of the smallest possible denomination, and everything else is display formatting.
The three units
Wei is the atom: the smallest indivisible unit. Gwei is one billion Wei (10⁹), used almost exclusively for quoting gas prices because it lands in a human-friendly range. BNB is one quintillion Wei (10¹⁸), the unit wallets and exchanges display.
So 1 BNB = 1,000,000,000 Gwei = 1,000,000,000,000,000,000 Wei. That raw balance above — 1.5 followed by eighteen digits of precision — is simply 1.5 BNB.
Why integers instead of decimals?
Computers handle fractional decimal numbers imprecisely — classic floating-point rounding would be catastrophic in a system moving billions of dollars. By storing every amount as a whole number of Wei, the chain's math is always exact. The decimal point you see in your wallet is drawn by software at display time, never stored.
Where this bites people
Developers and power users interacting with contracts directly must supply raw Wei values, and being off by one zero means sending ten times more or less than intended. Token amounts have the same trap: most BEP-20 tokens use 18 decimals like BNB, but some (notably certain stablecoins on other chains) use 6 or 8 — always check the token's decimals before doing math on raw values.
For quick conversions in either direction, use our Unit Converter — it computes with exact integer math, the same way the chain does.
Frequently asked questions
Why do wallets show slightly different balances than raw Wei suggests?
Display rounding. Wallets truncate the 18-decimal value for readability; the on-chain integer is the truth.
Do all tokens use 18 decimals?
Most on BSC do, but the standard allows any value — always read the token contract's decimals before doing math on raw amounts.