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TechnologyGenerated accuracy model review: 2026-05-06
CIDR Calculator accuracy and testing
This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.
Formula source
- Total addresses = 2^(32 - CIDR prefix). Subnet mask has prefix-length leading 1 bits. Usable hosts = max(total addresses - 2, 0).
Test cases
Default input regression check
Generated from the checked-in default inputs and calculate function.
Inputs
- CIDR Prefix: 24 /
Expected outputs
- Total Addresses: 256
- Subnet Mask: 255.255.255.0
- Wildcard Mask: 0.0.0.255
- Traditional Usable Hosts: 254
Known limitations
- This page documents the checked-in calculator logic and does not certify results for every real-world edge case.
- Use the result as a planning estimate unless the calculator page states a stricter purpose.
Assumptions
- This calculator covers IPv4 prefix math only.
- Usable hosts use the traditional network/broadcast subtraction model.
- Results are calculated locally in your browser.
Unit handling
- CIDR Prefix accepts values in /.
Rounding rules
- Number displays use up to 2 decimal places in the calculator UI.
- Input precision follows configured step values where provided.
Version history
1.0.0 - 2026-05-06
Generated accuracy and testing page from the current cidr-calculator calculator definition.
Change log
2026-05-06
Published default regression test documentation and metadata fallbacks for CIDR Calculator.
Calculator transparency
Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.