---
title: std.atof
summary: null
url: https://www.fastly.com/documentation/reference/vcl/functions/strings/std-atof
---


Takes a string (which represents a float) as an argument and returns its value.
Behaves as if calling `std.strtof()` with a base
of 10.

## Example

```vcl
if (std.atof(req.http.X-String) > 21.82) {
  set req.http.X-TheAnswer = "Found";
}
```