NetToolkit
Fast, free calculators and converters for network engineers.
About NetToolkit
NetToolkit is a free suite of network calculators for engineers: a subnet and CIDR calculator, an IP address converter (decimal, hexadecimal, and binary), a dBm-to-mW signal-power converter, and a data-transfer-time estimator. Enter your values and get instant, accurate results right in your browser — no sign-up.
Frequently asked questions
- What calculators are included?
- Four: a subnet / CIDR calculator, an IPv4 address converter, a signal-power (dBm/mW/W) converter, and a data-transfer-time estimator — all running locally in your browser.
- What does the subnet calculator show?
- For an IP and CIDR prefix it returns the netmask, wildcard mask, network and broadcast addresses, the usable host range, and the host count.
- How do I convert an IP address to binary or hex?
- Enter an IPv4 address in the IP converter and it shows the equivalent decimal (integer), hexadecimal, and dotted-binary forms instantly.
- What is dBm to mW conversion used for?
- Converting between decibel-milliwatts and milliwatts (and watts) is common in RF, fibre-optic, and wireless link-budget work; the converter handles all three units both ways.
- How do I estimate file transfer time?
- Enter a file size and a transfer rate (bandwidth) and the tool estimates how long the transfer takes — handy for backups, downloads, and link planning.
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