CIDR & Subnet Mask Converter
Convert between IPv4 prefix lengths and subnet masks, with wildcard masks and total address counts.
Local processing
This tool processes your input in your browser.
[IN/OUT] Conversion
Edit the prefix or subnet mask to update all values. Copying a prefix includes its leading slash.
Whole number from 0 to 32, without the slash.
Four decimal octets with contiguous leading 1 bits.
Read-only inverse of the subnet mask.
All addresses in the block, including network and broadcast addresses.
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