Tools

Everything here runs in your browser. Nothing is uploaded, nothing is logged, and every page works offline once loaded.

• Subnet calculator

  Paste any IPv4 CIDR and get the network address, host range, wildcard mask, and the number of addresses actually usable inside an AWS VPC subnet — the five AWS reserves included.

• NAT gateway cost calculator

  Hourly charges plus per-GB processing, and how much of it a gateway or interface VPC endpoint would remove. Shows the break-even point rather than a flat recommendation.