Calculadora de Subredes IP/CIDR
Ingresa un bloque CIDR IPv4 para calcular la máscara de subred, la dirección de red, la dirección de broadcast, el primer y último host, y el conteo de direcciones.
IPv4 CIDR
Initial support for IPv4.
Subnet
- Mask
- 255.255.255.0
- Network
- 192.168.1.0
- Broadcast
- 192.168.1.255
- First host
- 192.168.1.1
- Last host
- 192.168.1.254
- Addresses
- 256
- Usable hosts
- 254
How to calculate IPv4 subnets
Enter an IPv4 CIDR block to see the subnet mask, network address, broadcast address, host range, and address counts.
CIDR input
Use the format address/prefix, such as 192.168.1.10/24. Each octet must be between 0 and 255, and the prefix length must be between 0 and 32.
Host ranges
For most subnets, the first usable host is one address after the network and the last usable host is one before broadcast. /31 is treated as a two-address point-to-point link, and /32 as a single host route.
What to use it for
- Check network and broadcast addresses before configuring a device.
- Estimate usable host capacity for an IPv4 subnet.
- Verify whether a CIDR block is too broad or too narrow for a planned range.
Subnet notes
The calculator covers IPv4 CIDR only. IPv6 planning needs a different subnet model and is not part of this tool.
Preguntas frecuentes
Does it support IPv6?
No. This version is focused on IPv4 CIDR blocks.
Why does /31 show two usable hosts?
A /31 is commonly used for point-to-point links under RFC 3021, where both addresses can be used.
What does /32 mean?
It represents exactly one IPv4 address, often used as a host route.
Can I enter a range without CIDR?
No. Enter one IPv4 address with a CIDR prefix, such as 10.0.0.15/28.