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Lightning Math: mental math training in the browser
Lightning Math generates every question at runtime. Easy sticks to addition and subtraction within 20. Medium adds multiplication and larger numbers. Hard includes all four operations, bigger ranges, and exact division built from a product so the quotient is always a whole number.
Subtraction never produces a negative answer, and answers are typed as digits only. The game records every response time, then reports an average response alongside correct answers, mistakes and accuracy.
The countdown is yours to choose: 30 seconds for a sprint, 60 for a standard run, or 90 for a longer session. Pausing freezes the clock, and hidden tabs are paused automatically rather than silently costing you time.
How to play
- Choose a 30, 60 or 90 second countdown.
- Solve each question and type the answer, then press Enter or Submit.
- Only correct answers score. Wrong answers add mistakes and slow your pace.
- The clock pauses when you pause the game or switch tabs.
Tips
- For multiplication, break a number into tens and ones before multiplying.
- Division is easier when you ask “what times the divisor gives this number?”
- A steady 20 correct answers beats a rushed 12 with six mistakes.
Lightning Math FAQ
Are division answers always whole numbers?
Yes. Division questions are generated from a divisor and quotient, then multiplied to form the dividend, so the correct answer is always an integer.
Can I change the timer?
Yes. Pick 30, 60 or 90 seconds before a run. The timer is locked during that run and reused when you retry.
Does pausing stop the clock?
Yes. Pause freezes the countdown, and switching tabs pauses the run automatically. Resume when you are ready.