CIDR /6 Subnet Reference

A massive IPv4 subnet with 67.108.864 total addresses and 67.108.862 usable host addresses.

Subnet Mask252.0.0.0
Wildcard Mask3.255.255.255
Total IPs67.108.864
Usable Hosts67.108.862
Mask (Hex)FC000000
Host Bits26

Binary Breakdown

Subnet Mask11111100.00000000.00000000.00000000
Wildcard Mask00000011.11111111.11111111.11111111

Network bits (1s): 6 ·  Host bits (0s): 26

Common Uses for /6

  • Large network segment
  • ISP/enterprise allocation

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Enter any IP address with /6 prefix to calculate exact network details.

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Frequently Asked Questions

What is the subnet mask for /6?

The subnet mask for /6 is 252.0.0.0 (hex: FC000000). In binary: 11111100.00000000.00000000.00000000.

How many hosts does a /6 subnet support?

A /6 subnet has 67.108.864 total addresses. Subtract 2 (network + broadcast) = 67.108.862 usable host addresses.

What is the wildcard mask for /6?

The wildcard mask (inverse mask) for /6 is 3.255.255.255. Used in Cisco ACLs and OSPF configurations to match the host portion of an address.

What is CIDR /6 used for?

Large network segment. ISP/enterprise allocation.

Complete CIDR Reference Table /0–/32

PrefixSubnet MaskWildcardTotal IPsUsable Hosts
/00.0.0.0255.255.255.2554.294.967.2964.294.967.294
/1128.0.0.0127.255.255.2552.147.483.6482.147.483.646
/2192.0.0.063.255.255.2551.073.741.8241.073.741.822
/3224.0.0.031.255.255.255536.870.912536.870.910
/4240.0.0.015.255.255.255268.435.456268.435.454
/5248.0.0.07.255.255.255134.217.728134.217.726
/6252.0.0.03.255.255.25567.108.86467.108.862
/7254.0.0.01.255.255.25533.554.43233.554.430
/8255.0.0.00.255.255.25516.777.21616.777.214
/9255.128.0.00.127.255.2558.388.6088.388.606
/10255.192.0.00.63.255.2554.194.3044.194.302
/11255.224.0.00.31.255.2552.097.1522.097.150
/12255.240.0.00.15.255.2551.048.5761.048.574
/13255.248.0.00.7.255.255524.288524.286
/14255.252.0.00.3.255.255262.144262.142
/15255.254.0.00.1.255.255131.072131.070
/16255.255.0.00.0.255.25565.53665.534
/17255.255.128.00.0.127.25532.76832.766
/18255.255.192.00.0.63.25516.38416.382
/19255.255.224.00.0.31.2558.1928.190
/20255.255.240.00.0.15.2554.0964.094
/21255.255.248.00.0.7.2552.0482.046
/22255.255.252.00.0.3.2551.0241.022
/23255.255.254.00.0.1.255512510
/24255.255.255.00.0.0.255256254
/25255.255.255.1280.0.0.127128126
/26255.255.255.1920.0.0.636462
/27255.255.255.2240.0.0.313230
/28255.255.255.2400.0.0.151614
/29255.255.255.2480.0.0.786
/30255.255.255.2520.0.0.342
/31255.255.255.2540.0.0.122
/32255.255.255.2550.0.0.011