---
title: math.log10
summary: null
url: >-
  https://www.fastly.com/documentation/reference/vcl/functions/math-logexp/math-log10
---

```
FLOAT math.log10(FLOAT x)
```

**Available in:** all subroutines

Computes the base 10 logarithm of the input `x`.

## Example

```vcl
sub vcl_deliver {
  declare local var.foo FLOAT;
  set var.foo = math.log10(4294967296); # result: 9.633...
}
```