How to Learn Mental Math
☰ Contents
Free guides to doing arithmetic in your head. Each one explains why the shortcut works rather than just handing you a recipe — that is what makes a trick stick, and what tells you when it applies.
Every guide pairs with free practice in the game, because reading a shortcut and being able to use it are different skills.
Mental math practice
4 + 28 + 6 — which two make ten?
Every question here is from a lesson below. The free Daily Challenge
How do you learn mental math?
To learn mental math, get the times tables to instant recall first, then add one shortcut at a time and practice it daily in mixed questions for five minutes. Every trick in the other guides assumes 7 × 8 comes without thinking, and running a trick while working that out is what makes mental arithmetic feel impossible.
If recall is already solid, go straight to the shortcuts and pick two or three. Nobody uses all of them — people who are quick tend to have a handful they reach for automatically.
Fractions and percentages are the same idea in two notations, so they read well together: a percentage is a fraction whose denominator everyone has already agreed on.
Practice in the game
Math Challenge is a free mental-math game: swipe to answer, with difficulty that adapts to what you keep missing. It has 35 practice topics and 36 illustrated Magic Tricks lessons that teach the reasoning behind each shortcut. The Daily Challenge is free and needs no account.
Now you
One more than 7
One more than 3
Your turn
Three to try — tap what you get.
7 × 8
Half of 3/4
10% of 250