IP Calculator Support

A free IPv4 subnet calculator for iPhone and iPad

Need help? Email andrew@agar.ai with your question, feedback or bug report, and include the address and prefix you were using if it's about a calculation.

Quick answers

Can I type a prefix with the address? Yes. Enter 10.0.0.1/8 or 10.0.0.1 255.0.0.0 and the prefix is picked up automatically.

Why does a /31 show 2 usable hosts? /31 networks are used for point-to-point links (RFC 3021), where both addresses are usable. A /32 is a single host.

How do I copy a result? Tap any value to copy it. On the Range tab, "Copy all" copies every CIDR block at once.

Does the app need an internet connection? No. Every calculation runs on your device.

Privacy

IP Calculator is free, has no ads and collects no data. Read the full privacy policy.