IPv6 Expand
Expand all eight groups of an IPv6 address.
Expanding an IPv6 address restores every one of the eight 16-bit groups and their leading zeros, turning 2001:db8::1 into 2001:0db8:0000:0000:0000:0000:0000:0001. The fixed-width form is what you want when comparing or sorting addresses as text.
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How IPv6 Expand works
What it does
Expand all eight groups of an IPv6 address.
What you get
All eight IPv6 groups, including leading zeros.
On your device
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What if a check cannot finish?
Confirm your input and try again. A timeout, blocked request, or unavailable provider is not proof that a domain is broken. Internet measurements and third-party services have limits.
IPv6 Expand — frequently asked questions
Why expand at all?
Because two different-looking strings can be the same address. Expanding both produces a single fixed-width form that plain string comparison handles correctly.
Is the expanded form valid to use?
Yes, everywhere — it is simply more verbose. RFC 5952 prefers the compressed form for display.
How many characters is a full IPv6 address?
Thirty-nine: eight groups of four hex digits plus the seven colons between them.