# /29 Subnet Mask (255.255.255.248) – Hosts, Range & FAQ > The /29 subnet mask is 255.255.255.248. A /29 block holds 8 addresses with 6 usable hosts — ranges, wildcard, binary math and FAQs. - Page URL: https://itinsighthub.com/subnet/29/ - Markdown variant of this page: append `?format=md` to any URL on this site or send `Accept: text/markdown`. - Full site index for AI assistants: https://itinsighthub.com/llms.txt - Full site export: https://itinsighthub.com/llms-full.txt # /29 Subnet Mask ReferenceIPv4 Eight addresses wide, six of them usable: mask 255.255.255.248. The /29 is the polite way to hand someone 'a few public IPs', enough for a router, a firewall pair, and a virtual IP or two. The /29 subnet mask is 255.255.255.248, equivalent to 0.0.0.7 as a wildcard. A /29 block contains 8 IP addresses (6 usable hosts). ## /29 facts at a glance - **Subnet mask:** 255.255.255.248 - **Wildcard mask:** 0.0.0.7 - **Binary mask:** 11111111.11111111.11111111.11111000 - **Total addresses:** 8 - **Usable hosts:** 6 (excludes network & broadcast) - **Block size:** 8 addresses (23) - **Typical role:** Subnets, VLANs and WAN links ## Example /29 networks Three consecutive /29 blocks, starting at the /29 boundary that contains 198.51.100.0: | Network | Usable range | Usable hosts | | --- | --- | --- | | 198.51.100.0/29 | 198.51.100.1 – 198.51.100.6 | 6 | | 198.51.100.8/29 | 198.51.100.9 – 198.51.100.14 | 6 | | 198.51.100.16/29 | 198.51.100.17 – 198.51.100.22 | 6 | ## How to calculate a /29 mask A /29 mask sets the first 29 bits of a 32-bit number to 1 and leaves the remaining 3 bits as 0. In binary that reads `11111111.11111111.11111111.11111000`, which converts to dotted decimal `255.255.255.248`. Each block covers a contiguous run of 23 = 8 addresses, and every block starts at a multiple of that size. The wildcard simply flips every bit, giving `0.0.0.7`. ## Where /29 is used - Small public blocks leased to businesses by their ISP. - A DMZ with just a couple of externally reachable services. - Outbound NAT pools with several source addresses. In the .0 block, hosts occupy .1 through .6 while .0 names the network and .7 broadcasts. Address efficiency is 75 percent: better than a /30's 50 percent, though still no match for RFC 3021's /31 on pure point-to-point duty. ## Frequently asked questions **How many usable hosts are in a /29?** 6 of 8 total addresses. **What is the subnet mask for a /29?** 255.255.255.248, wildcard 0.0.0.7: five fixed bits in the last octet leave three host bits. **How many /29s fit in a /24?** Thirty-two, since each consumes eight fourth-octet values. **If my ISP gives me x.x.x.0/29, what can I actually use?** Addresses .1 through .6 on your edge devices; .0 stays the network identifier and .7 remains the broadcast within that link segment. ## Open this block in a calculator [Open the /29 block in the subnet calculator](https://itinsighthub.com/subnet-calculator/?q=198.51.100.0%2F29) [Get the /29 wildcard mask →](https://itinsighthub.com/wildcard-mask-calculator/?q=%2F29) ### Related prefixes [/24](https://itinsighthub.com/subnet/24/)[/26](https://itinsighthub.com/subnet/26/)[/28](https://itinsighthub.com/subnet/28/)[/30](https://itinsighthub.com/subnet/30/) ← /28 subnet mask /30 subnet mask → --- © 2026 ITInsightHub · [About](https://itinsighthub.com/about/) · [Contact](https://itinsighthub.com/contact/) · [Privacy](https://itinsighthub.com/privacy/)