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

```
STRING std.tolower(STRING s)
```

**Available in:** all subroutines

Changes the case of a string to lowercase. For example, `std.tolower("HELLO");` 
will return `"hello"`.

## Example

```vcl
set beresp.http.x-nice = std.tolower("VerY");
```