---
title: Map IPv6 addresses to IPv4 address space
summary: Create an identifier that looks like an IPv4 address if the user has made their request using IPv6. Useful for origin servers that require an IPv4 address for some reason.
url: https://www.fastly.com/documentation/solutions/examples/ipv6-to-ipv4-translation
---

Create an identifier that looks like an IPv4 address if the user has made their request using IPv6. Useful for origin servers that require an IPv4 address for some reason.

## VCL

[Try it in Fastly Fiddle](https://fiddle.fastly.dev/f1afbd0f)

## Compute

### Rust

[Try it in Fastly Fiddle](https://fiddle.fastly.dev/46e535a6)

### Javascript

[Try it in Fastly Fiddle](https://fiddle.fastly.dev/bf00b4ff)