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TechnologyGenerated accuracy model review: 2026-05-06
IP Subnet 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
- 1. **Netmask:** Derived from CIDR (e.g., /24 = 255.255.255.0). 2. **Network Address:** Bitwise AND of IP and Netmask. 3. **Broadcast Address:** Bitwise OR of Network Address and inverted Netmask. 4. **Hosts:** 2^(32 - CIDR) - 2.
Test cases
Default input regression check
Generated from the checked-in default inputs and calculate function.
Inputs
- IP Address: 192.168.1.1
- CIDR: 24 /
Expected outputs
- Network Address: 192.168.1.0/24
- Subnet Mask: 255.255.255.0
- Usable IP Range: 192.168.1.1 - 192.168.1.254
- Broadcast Address: 192.168.1.255
- 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 is for IPv4 only and expects a dotted-quad address with four octets.
- Usable-host math follows the traditional 2^(32 - CIDR) - 2 rule, so /31 and /32 show no traditional host range.
- CIDR must be an integer from 0 through 32, and each IP octet must be an integer from 0 through 255.
Unit handling
- IP Address accepts text values.
- CIDR accepts values in /.
Rounding rules
- Number displays use up to 2 decimal places in the calculator UI.
Version history
1.0.0 - 2026-05-06
Generated accuracy and testing page from the current ip-subnet-calculator calculator definition.
Change log
2026-05-06
Published default regression test documentation and metadata fallbacks for IP Subnet Calculator.
Calculator transparency
Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.