How it works
Complete the job in three clear steps
- Paste the source value and choose the conversion settings.
- Run the operation locally in this browser.
- Review, copy, or download the generated result.
Private browser data tool
IPv6 Subnet Calculator
Calculate the network boundary, last address, prefix, host bits, and address count for an IPv6 CIDR block.
Free to use Input and results stay in this browser. Lucaden does not send them to a conversion API.
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Important
Check the result before relying on it
Scan-test generated codes before printing or distribution. A generated barcode does not register identifier ownership, and decoded external links should be checked before opening.
Practical details
What this Lucaden tool does
Calculate the network boundary, last address, prefix, host bits, and address count for an IPv6 CIDR block.
This is an independent Lucaden implementation. CyberChef and IT-Tools are credited as product references; their application code is not copied or bundled.
Included capabilities
- Prefixes /0 through /128
- 128-bit BigInt math
- Network and final address
- Exact address count
Useful for
- Plan IPv6 allocation
- Review firewall ranges
- Document subnets
- Validate CIDR boundaries
Questions
About this tool
Does this tool upload my data?
No. The transformation runs on this device with browser APIs or locally loaded open-source libraries.
Is the output suitable for production use?
Validate security, networking, certificate, and data-conversion output against the application that will consume it.
Open-source foundations
Built transparently
Lucaden documents its standards sources, architectural references, and permissive runtime dependencies while keeping this workspace consistent with the Lucaden interface.