ipcalc takes an IP address and netmask and calculates the resulting broadcast, network, Cisco wildcard mask, and host range. By giving a second netmask, you can design subnets and supernets. It is also intended to be a teaching tool and presents the subnetting results as easy-to-understand binary values.
|IP Calculator Results.|
DNS Propagation Checkers
whatsmydns.net lets you instantly perform a DNS lookup to check a domain names current IP address and DNS record information against multiple name servers located in different parts of the world. This allows you to check the current state of DNS propagation after having made changes to your domains records.
dnschecker.org is a similar tool.
|DNS Checker Results.|
Test Website Performance
Use webpagetest.org to run a free website speed test from multiple locations around the globe using real browsers (IE and Chrome) and at real consumer connection speeds. You can run simple tests or perform advanced testing including multi-step transactions, video capture, content blocking and much more. Your results will provide rich diagnostic information including resource loading waterfall charts, Page Speed optimization checks and suggestions for improvements.
|Website Performance Test Results.|