CIDR/Subnet Calculator - Free, Instant, In Your Browser
Enter a CIDR block like 192.168.1.0/24 to see its full subnet breakdown.
How to use CIDR Calculator
- 1Paste your text or data into the input box above.
- 2CIDR Calculator runs instantly, right in your browser.
- 3Copy the result or use it directly.
Your file is processed in your browser and is never uploaded.
Frequently Asked Questions
What format is expected?
An IPv4 address followed by a slash and prefix length, e.g. 10.0.0.0/16.
Does this support IPv6?
Not currently - this tool works with IPv4 CIDR blocks only.