Dual N-Back - Brain Training Online

Mental Math — sharpen your arithmetic, one problem at a time

A fast, adaptive arithmetic workout. Free, in your browser, no signup to start.

See it in action

How it works

Equation appears

A math problem shows up — addition, subtraction, multiplication or division.

You answer fast

Work it out in your head and answer before the clock runs out.

Difficulty adapts

Answer well and the numbers grow; slip up and the level eases back down.

Four operations, one adaptive level

+
Addition
Subtraction
×
Multiplication
÷
Division

Train each operation on its own, or switch to Mix mode, which shuffles all four so you can't predict what's next.

Part of the BrainScale training suite, trained by people in 120+ countries since 2011.

What is Mental Math training?

Mental Math is a timed arithmetic exercise: solve addition, subtraction, multiplication and division problems entirely in your head, with no pen, paper, or calculator. Each round asks you to work quickly and accurately, and the difficulty follows your performance — the numbers grow larger and the carries and borrows get trickier as you improve.

How the exercise works

  • An equation appears using one of four operations, or a random mix of all four
  • You answer before time runs out — speed and accuracy both count
  • The level is two digit-length settings, one per operand, so difficulty scales independently on each side
  • Answer well and digit counts grow; miss a few and the level eases back down
  • Sessions are short — a few focused minutes a day is the point

Why train mental arithmetic?

  • Builds real numeracy — the kind you actually use for bills, tips, and quick estimates
  • Loads working memory, since you hold partial results in mind while you compute
  • Sharpens processing speed under light time pressure
  • Adapts to your level automatically, so it stays challenging without becoming frustrating

Regular short sessions beat occasional long ones — consistency is what moves your level.

Who it's for

  • Anyone who wants faster, more confident everyday arithmetic
  • Students building number fluency and speed under time pressure
  • People who want a quick, focused brain workout that fits in a coffee break
  • Anyone building a daily training habit — pair it with streaks

Frequently asked questions

What is Mental Math training?

Mental Math is a timed arithmetic exercise on BrainScale. You solve addition, subtraction, multiplication and division problems in your head — no pen, paper, or calculator — before the clock runs out. It trains numeracy, working memory and mental processing speed together.

Is Mental Math training free to play?

Yes. Mental Math is free to play with no signup required to start. Creating a free account adds progress tracking and streaks; a premium plan removes free-tier session limits.

How does the difficulty level adapt?

Each problem uses a level made of two digit-length settings, one per operand. Solve problems correctly and quickly, and the digit counts grow, so numbers get larger and carries/borrows get harder to track mentally. Slip up, and the level eases back down automatically.

Which operations does Mental Math include?

Addition, subtraction, multiplication and division, each trainable on its own, plus a Mix mode that shuffles all four operations together so you cannot predict which one is coming next.

How often should I practice mental math?

Short, frequent sessions beat occasional long ones. A few focused minutes a day is enough to keep pushing your level up, and pairs well with a daily training streak.

Start training — it's free