> Free Network and Developer Tools_

IP & Subnetting

• Subnet Calculator

  Network, broadcast, host range and mask for any IPv4 subnet.

• CIDR Calculator

  Convert CIDR blocks to IP ranges and ranges back to CIDR.

• IP Calculator

  See any IP address and mask in binary, decimal and hex.

• IPv6 Subnet Calculator

  Split IPv6 prefixes and count /64 networks.

• Subnet Cheat Sheet

  Every prefix from /0 to /32 with mask and host count.

• CIDR Notation

  What the slash means, explained with examples.

Encoding

• Base64 Decode

  Turn Base64 back into text or a file.

• Base64 Encode

  Convert text or files to Base64.

Popular subnets

• /24
• /16
• /27
• /30
• 10.0.0.0/8
• 192.168.0.0/16

Why these tools

Private by design. Every tool runs entirely in your browser. The addresses, strings and files you enter are never sent to a server.

Correct and explained. Results show the math behind them, so you can verify the answer or learn it for CCNA, Network+ or a job interview.

Shareable. The URL keeps your input, so you can bookmark a calculation or send it to a teammate.

Fast everywhere. Pages load instantly, work offline, support dark mode and can be used entirely from the keyboard.