Network & API
IP / Subnet CalculatorOnline Developer Tool
Compute IPv4 and IPv6 CIDR details: netmask, wildcard, broadcast, first and last host, and subnet size. Runs locally in your browser.
About IP / Subnet Calculator
Compute IPv4 and IPv6 CIDR details: netmask, wildcard, broadcast, first and last host, and subnet size. Runs locally in your browser. Runs entirely in your browser — no installation, no account required to try it.
Key Features
- subnet calculator
- cidr calculator
- ip calculator
- netmask
- ipv6 subnet
- network calculator
- ip range
- Runs in your browser — no install
- Free to use, always
How to Use IP / Subnet Calculator
- 01
Open the tool
Click "Use IP / Subnet Calculator Free" above — no download or account required.
- 02
Enter your data
Paste or type your input directly in the browser. Processing happens locally on your device.
- 03
Copy the result
Get your output instantly. Copy it, download it, or keep working in the same tab.
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