---
url: https://react-ui.bas.dev/formatting/numbers.md
---
# Numbers

Counts, decimals, percentages, money, sizes and token counts, each in the notation of the region.

```ts
import { formatBytes, formatDecimal, formatMoney, formatNumber, formatPercent, formatTokens, formatUsdSignificant } from '@basmilius/react-ui/format';
```

| Function | Writes |
| --- | --- |
| `formatNumber(value)` | A whole number, grouped the way the region groups one: `1,234,568` or `1.234.568`. It rounds first. |
| `formatDecimal(value)` | The same with at most one decimal, where the fraction is the part that means something. |
| `formatPercent(value)` | A percentage of a value that is already a percent: one decimal under ten, where the difference still shows, and whole above. `4.3%`, `43%`. |
| `formatMoney(value, currency, maximumFractionDigits?)` | An amount in the currency it is already in, with the narrow symbol, so a Dutch region writes `$ 5.480,96` and not `US$ 5.480,96`. |
| `formatUsdSignificant(value)` | Dollars to three significant digits, for a list of amounts that runs from a fraction of a cent to tens of dollars. |
| `formatTokens(value)` | A size rather than a count: `1.2M`, `412K`, `640`. |
| `formatBytes(bytes, whole?)` | A file size in B, KB, MB, GB or TB, with one decimal under ten above a kilobyte. `whole` rounds for a column with no room for a decimal. |

None of these converts. `formatMoney` never changes the currency, and `formatBytes` counts in steps of 1024.