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# Math.fround()

The **`Math.fround()`** function returns the nearest [32-bit single precision](https://en.wikipedia.org/wiki/Single-precision_floating-point_format) float representation of a number.

## Syntax

```js
Math.fround(doubleFloat)
```

### Parameters

- `doubleFloat`
  - : A number.

### Return value

The nearest [32-bit single precision](https://en.wikipedia.org/wiki/Single-precision_floating-point_format) float representation of `x`.

## Description

JavaScript uses 64-bit double floating-point numbers internally, which offer a very high precision. However, sometimes you may be working with 32-bit floating-point numbers, for example if you are reading values from a `Float32Array`. This can create confusion: checking a 64-bit float and a 32-bit float for equality may fail even though the numbers are seemingly identical.

To solve this, `Math.fround()` can be used to cast the 64-bit float to a 32-bit float. Internally, JavaScript continues to treat the number as a 64-bit float, it just performs a "round to even" on the 23rd bit of the mantissa, and sets all following mantissa bits to `0`. If the number is outside the range of a 32-bit float, `Infinity` or `-Infinity` is returned.

Because `fround()` is a static method of `Math`, you always use it as `Math.fround()`, rather than as a method of a `Math` object you created (`Math` is not a constructor).
