Square Root Logo   Square Root Pro

Learn to calculate square roots in your head quickly!

Square roots are often found in math & science and quick calculation is sometimes necessary in order to tackle common questions.

© IdeasOnANapkin

Download the App
-- users are using the app now!
-- users are using the app now!


Quiz Mode

Test your square root knowledge against random numbers. If you need help, a simple tutorial waits nearby.

Learn Mode

Look-up square roots to certain numbers. A five-step tutorial is available on how to calculate in your head.


Switch easily between English, Spanish, French, German & Chinese (Mandarin). Fully internationalized numeric system.


Track your progress with colorful visual elements. Share your successes via email or social media.


Works well on a large tablet (iPad Pro/Galaxy Tab) down to a small phone (iPhone SE/Google Pixel).

Dark Mode

Easy to operate in regular or dark mode.

Crafted specifically for each platform

Apps are hand-written using the latest native IDEs & technologies: Jetpack Compose & SwiftUI.

Frequently Asked Questions

How does it work?

This app lets you calculate square roots to reasonable accuracy by using this method:


where c^2 is close to zero and can be dismissed. This method helps you to mentally calculate an answer out to two decimal places, close enough for most scientific research.

Why should I learn this?

Professor Jo Boaler of Stanford University says students learn math best when they work on problems they enjoy rather than exercises and drills they fear. By gamifying this process, you can learn skills that are useful in everyday life in addition to impressing your friends & colleagues.

Why is math important?

Mathematics is essential to our world, so mathematical knowledge can apply to many situations. The importance of math is not only crucial for scientists or engineers, but it helps to develop skills in order to analyze data and recognize patterns every day.

Go and learn something amazing!