Description: Debuggex is a free online visual regex tester. It allows you to visually construct regex patterns and test them against input strings to see if there is a match.
Type: software
Pricing: Free
Description: Wolfram Alpha is a computational knowledge engine that allows users to get instant expert-level answers to questions on math, science, and many other topics by typing queries in plain language. It understands and computes answers across many domains.
Type: software