# IPv6 Expander & Compressor

URL: https://phishdestroy.io/developer-tools/ipv6-compressor
Category: General dev
Where it runs: Runs locally (nothing you enter is uploaded)

Expand a shortened IPv6 address to its full eight groups, or shorten it with ::. Logs, blocklists and RDAP records often store different forms of the same address, which makes plain-text searches miss.

## Example input

Shortened address

```
2001:db8::8a2e:370:7334
```

Load example runs Expand and gives 2001:0db8:0000:0000:0000:8a2e:0370:7334.

## FAQ

### What do Expand and Compress do?

Expand fills in the zero groups hidden by :: and pads every group to four hex digits. Compress shortens all-zero groups to 0 and replaces the first run of two or more of them with ::.

### Is the compressed form RFC 5952 canonical?

Not always. Compress keeps one leading zero in groups such as 0db8 or 0001 (giving 2001:0db8::01 instead of 2001:db8::1) and shortens the first zero run rather than the longest. Letter case is kept, input is not validated, and embedded IPv4 (::ffff:192.0.2.1) is expanded incorrectly.

### Is the address sent anywhere?

No. Both operations are string processing in your browser.

## Related tools

- [IPv6 ULA Generator](https://phishdestroy.io/developer-tools/ipv6-ula-generator)
- [CIDR / Subnet Calculator](https://phishdestroy.io/developer-tools/cidr-subnet-calculator)
- [IPv4 Address Converter](https://phishdestroy.io/developer-tools/ip-address-converter)
- [Abuse Contact Lookup](https://phishdestroy.io/developer-tools/abuse-contact-lookup)
- [IOC Converter](https://phishdestroy.io/developer-tools/ioc-converter)

All tools: https://phishdestroy.io/developer-tools