Subnet Mask to CIDR

Convert subnet masks to CIDR notation. Free, instant.

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How to Use Subnet Mask to CIDR

1

Enter subnet mask.

2

Get CIDR notation.

3

Copy or download your result.

Frequently Asked Questions

Common subnets?

/24 = 255.255.255.0 (254 hosts). /16 = 255.255.0.0 (65534 hosts).