---
title: req.vcl
summary: null
url: >-
  https://www.fastly.com/documentation/reference/vcl/variables/miscellaneous/req-vcl
---

**Type:** STRING  
**Access:** read-only

**Available in:** 

The version of the service currently executing. Takes the form:

```
{serviceID}.{version}_{generation}-{hash}
```

Where:

- `{serviceID}` is the ID of the Fastly service.
- `{version}` is the service version, an integer that increases each time the service configuration is cloned.
- `{generation}` is an integer that increases each time the service is purged.  See `req.vcl.generation`.
- `{hash}` is a hashsum of the VCL code.