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Network & IP Calculation Tools

IPv6 Validator

Validate IPv6 by parsing each group, with proper handling of ::, hexadecimal group counts, and embedded IPv4 tails.

Leading and trailing spaces are ignored; the address itself is not corrected automatically.

Validate full, compressed, and IPv4-mapped IPv6 addresses and view expanded and normalized compressed forms.

Your input is processed only in your browser and is never uploaded to a server.

What this tool does

Validate an IPv6 address and see its expanded and compressed forms. Supports full addresses, a single :: abbreviation, loopback, unspecified and link-local addresses, and addresses ending with a valid IPv4 address.

  • Each regular hexadecimal group must contain one to four characters from 0-9, a-f, or A-F.
  • :: may appear at most once and must represent at least one all-zero group.
  • Expanded output always uses eight four-digit lowercase hexadecimal groups. Compressed output uses the longest run of zero groups, choosing the leftmost run in a tie.

How to use it

  1. Enter a full or compressed IPv6 address.
  2. Click Validate IPv6.
  3. View the validation status, expanded address, and compressed address.
  4. Copy the normalized representation you need.

How it works

The expanded form has eight groups of four hexadecimal digits. Compression replaces the longest run of zero groups with ::, choosing the leftmost run in a tie. An IPv4 ending appears in hexadecimal in the normalized result.

Examples

  • 2001:db8::1 → Expands to 2001:0db8:0000:0000:0000:0000:0000:0001.
  • ::ffff:192.168.1.1 → Valid and can be normalized as ::ffff:c0a8:101.
  • 2001::db8::1 → Invalid because :: appears twice.

Common uses

  • Validate IPv6 strings in network configurations or documentation.
  • Normalize an address between expanded and shortened forms.
  • Check whether an IPv4-mapped IPv6 tail is valid.

Privacy

Your input and results stay in your browser and are not uploaded or saved automatically. Copy any results you want to keep and save them yourself before leaving the page.

IPv6 Validator Features

Validate full, compressed, and IPv4-mapped IPv6 addresses and view expanded and normalized compressed forms. Useful for network planning, configuration checks, and troubleshooting; results can be reviewed and copied immediately.

FAQ

How many bits are in an IPv6 address?

An IPv6 address contains 128 bits and is typically written as eight 16-bit hexadecimal groups.

What does :: mean in an IPv6 address?

It represents one or more consecutive all-zero groups and can be used only once in an address.

What address is ::1?

::1 is the IPv6 loopback address, equivalent to 127.0.0.1 in IPv4.

Does IPv6 validation connect to the network?

No. The page only parses the input string; it does not query routing, DNS, WHOIS, address ownership, or connectivity.

IPv4 Validator

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