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IPv6 Address Compressor, Expander & Subnet Inspector

Compress standard RFC 5952 IPv6 addresses (zero-compression ::), expand full 8-hextet representations, convert to integer, and generate reverse DNS PTR strings.

RFC 5952 Canonical Engine
Address ScopeGlobal Unicast (2000::/3 Internet Routable)
Prefix Length/64
Zero CompressionActive (:: Applied)
Hex Groups8 Hextets (128-bit)
RFC 5952 Compressed Format
2001:db8::ff00:42:8329/64
Fully Expanded (8 Hextets)
2001:0db8:0000:0000:0000:ff00:0042:8329/64
128-bit Decimal BigInteger
42540766411282592856904265327123268393
Reverse DNS (ip6.arpa PTR Record)
9.2.3.8.2.4.0.0.0.0.f.f.0.0.0.0.0.0.0.0.0.0.0.0.8.b.d.0.1.0.0.2.ip6.arpa.

Private Local Calculation

Your network architecture and internal IPv6 subnet topology are parsed and transformed locally without leaving your browser sandbox.

RFC 5952 Standards Compliance

Applies canonical compression: collapses the longest contiguous sequence of zeros, suppresses leading zeros, and outputs lowercase hex.

Instant Multi-Format Output

Simultaneously produces 128-bit decimal integers, fully padded 32-digit expansions, and reverse DNS PTR records for BIND and Unbound.

Technical Reference & Architecture Guide

RFC 5952 IPv6 Compression & Subnetting Guide — Reference Guide

Comprehensive guide to IPv6 address representations, RFC 5952 canonical compression rules, EUI-64 generation, and reverse DNS PTR construction.

Key Parameters & Controls

ipv6Addressstring

128-bit IPv6 address with optional CIDR routing prefix length.

compressionRuleenum ('RFC 5952' | 'None')

Canonical zero-suppression replacing the longest consecutive run of zeros with ::.

outputFormatenum ('compressed' | 'expanded' | 'decimal')

Representation format: compressed, 8 full hextets, or 128-bit decimal integer.

cidrPrefixnumber (0-128)

Subnet routing prefix length defining network vs interface ID portions.

Pro Tips & Best Practices

RFC 5952 mandates that double colons (::) must only compress runs of two or more consecutive 0 hextets.

Hexadecimal characters a-f must always be lowercase in canonical representations.

Reverse DNS queries require reversing all 32 hex nibbles followed by the .ip6.arpa domain.

Common Gotchas & Troubleshooting

An IPv6 address can contain at most ONE instance of :: to avoid ambiguous hextet counts.

Ensure :: is properly expanded into the missing number of 0000 hextets.

Frequently Asked Questions

What is RFC 5952?▼

It is the official IETF standard defining the single canonical textual representation of IPv6 addresses.

What happens if two zero runs are of equal length?▼

RFC 5952 specifies that the first run of zeros must be compressed with ::.

Can I convert IPv6 addresses to 128-bit decimal integers?▼

Yes, the tool calculates the exact 128-bit BigInt decimal equivalent.

How does reverse DNS work for IPv6?▼

Each 4-bit nibble of the 32 hex digits is separated by dots in reverse order ending in .ip6.arpa.

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