CIDR / Subnet Calculator
IPv4- og IPv6-netværk
| Family | IPv4 |
| Address | 192.168.1.10 |
| Prefix | /24 |
| Network | 192.168.1.0 |
| Broadcast | 192.168.1.255 |
| Subnet mask | 255.255.255.0 |
| Wildcard | 0.0.0.255 |
| First host | 192.168.1.1 |
| Last host | 192.168.1.254 |
| Total addresses | 256 |
| Usable hosts | 254 |
Om dette værktøj
Compute network details for any IPv4 or IPv6 CIDR block - network and broadcast addresses, host range, subnet mask, wildcard mask and total/usable host count. The right tool for planning subnets, debugging firewall rules, or understanding what a /24 actually contains.
Privvert handles both IPv4 (10.0.0.0/24, 192.168.1.0/16) and IPv6 (2001:db8::/48) CIDR notation. All math runs in your browser.
Funktioner
- IPv4 and IPv6 support
- Network, broadcast, first/last host addresses
- Subnet mask and wildcard mask
- Total and usable address counts
- Binary breakdown of network and host bits
- Browser-only - runs locally
- Free and unlimited
- Shows total addresses, usable hosts and the broadcast address
Sådan bruger du det
- Type a CIDR like 10.0.0.0/24 or 2001:db8::/48.
- Read the calculated rows.
Alt sker inde i din browser med JavaScript og WebAssembly. Dine filer bliver aldrig uploadet, aldrig gemt og aldrig set af os.
Ofte stillede spørgsmål
IPv6 doesn't reserve network/broadcast addresses the way IPv4 does, so all addresses in a block are usable for hosts. The 'total' and 'usable' counts are the same.
Subnet mask has 1s for the network portion (255.255.255.0 = /24). Wildcard mask is the inverse, with 1s for the host portion (0.0.0.255). ACLs and OSPF use wildcards; everything else uses the mask.
/32 is a single host (one address). /31 is two addresses, used for point-to-point links per RFC 3021. Below /30 traditional rules don't reserve network/broadcast addresses.
Reverse lookup (is X.X.X.X inside CIDR Y/Z) is on the roadmap. For now, use the network and broadcast columns to compare manually.
They're two ways of writing the same subnet mask. CIDR notation (the /24) counts how many leading bits are network bits; dotted-decimal notation spells out the mask as four bytes. The tool shows both for every input.
Yes. IPv6 CIDR ranges are parsed the same way - the only practical difference is that even modest IPv6 prefixes contain absurdly large address counts, which the tool displays in scientific notation.