IPv6 CIDR Prefix Parser
Local ProcessingAnalyze IPv6 CIDR prefixes (/0 to /128) showing network address, final address, and total address count.
How It Works & Processing Standards
Analyze IPv6 CIDR prefixes (/0 to /128) showing network address, final address, and total address count.
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Current Limits
- Maximum input length: 100,000 characters
IPv6 blocks hold so many addresses that ordinary calculators lose digits. This tool uses 128-bit integers to show the exact range and count for blocks such as /48 or /64.
What You Can Do
- CIDR analysis
- Network, last address, prefix and total address count.
- Prefix range
- Just the start and end addresses of the block.
How to Use IPv6 CIDR Prefix Parser
- 1Choose a taskCIDR analysis or prefix range.
- 2Enter the CIDRFor example 2001:db8::/48.
- 3Read the resultCopy the range and count.
Examples
/48 analysis
Input: 2001:db8::/48
Result: Network 2001:db8::, last 2001:db8:0:ffff:ffff:ffff:ffff:ffff, 1208925819614629174706176 addresses
/64 range
Input: 2001:db8:abcd::/64
Result: 2001:db8:abcd:: – 2001:db8:abcd:0:ffff:ffff:ffff:ffff (18446744073709551616 addresses)
Common Use Cases
- Checking the range of an IPv6 block from your ISP or cloud
- Reviewing IPv6 prefixes for firewall rules
Frequently Asked Questions (FAQ)
Why is /64 the usual subnet?
IPv6 stateless autoconfiguration (SLAAC) uses the last 64 bits as the interface identifier, so LANs are split into /64s.