# Reference: `sushi` Math

The math module provides BigInt-first helpers for DeFi amounts and ratios.

## Exports

| Export | Purpose |
|---|---|
| `Fraction` | Rational number with bigint numerator/denominator. |
| `Percent` | Percent helper built on `Fraction`. |
| `ZERO`, `ONE`, `TWO`, etc. | Common bigint constants. |
| `MAX_UINT256`, `MAX_UINT128` | Common uint bounds. |
| `abs`, `difference`, `maximum`, `minimum` | BigInt helpers. |
| `numberToBigInt` | Convert safe numbers to bigint. |
| `sqrt` | Integer square root. |

## Fraction

```ts twoslash
import { Fraction, Percent } from 'sushi'

const ratio = new Fraction({ numerator: 1n, denominator: 3n })
const doubled = ratio.mul(2n)
const slippage = new Percent({ numerator: 5n, denominator: 1000n })
```

| Method/property | Purpose |
|---|---|
| `quotient`, `remainder` | Integer division parts. |
| `invert` | Swap numerator and denominator. |
| `add`, `sub`, `mul`, `div` | Fraction arithmetic. |
| `lt`, `lte`, `eq`, `gte`, `gt`, `neq` | Comparisons. |
| `toNumber` | Convert to JavaScript number. |
| `toString`, `toSignificant` | Display formatting. |
| `toJSON` | Serialize numerator/denominator. |
| `asFraction` | Return a plain `Fraction` from subclasses. |

BigInt math preserves integer precision. `toString` and `toSignificant` format directly from the fraction's bigint values with the requested precision. `toNumber` converts to a JavaScript number and can lose precision, so it should be used for display rather than critical accounting.