errProof is described as 'The website has a lot of useful and unique tools' and is an website in the Education & Reference category. There are more than 100 alternatives to errProof, not only websites but also apps for a variety of platforms, including Windows, Mac, Android and Linux. The best alternative is SpeedCrunch, which is both free and Open Source. Other great sites and apps similar to errProof are Wolfram Alpha (Freemium), Pastebin.com (Freemium), Qalculate! (Free, Open Source) and Write.as (Freemium, Open Source).
A modern, scientific calculator that is easy to use. While other calculators display only one number at a time, this one shows you the whole expression you are inputting, leading to a much more user friendly experience.
An easy to use scientific calculator with many advanced features to help you solve algebra, trigonometry, and engineering math problems. The calculator comes with six attractive color schemes and a side bar that slides open for additional functionality.