Usable Hosts
Free Usable Hosts calculator with clear step-by-step results.
About Usable Hosts
Usable hosts subtract the network and broadcast addresses.
Formula
Formula
Hosts = 2^(32−prefix) − 2
Worked example
With the default values below, Usable Hosts returns Usable Hosts of 254.00. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Prefix lengthaccepts 1–31
- 24
Results
- Usable Hosts
- 254.00
- Total Addresses
- 256.00
- Subnet Mask
- 0.255.255.255
Step by step
- 1Values used
- 2Formula
- 3Usable Hosts= 254
- 4Total Addresses= 256
- 5Subnet Mask= 0.255.255.255
Assumptions and limits
- The result is derived only from the single input listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How does this calculator work?
Usable hosts subtract the network and broadcast addresses.
Why does this matter?
A /31 has no usable hosts under classic rules.