Race the clock — can your brain do math faster than time runs out?
🕹️How to Play
- 1An arithmetic problem appears on screen — solve it fast!
- 2Type your answer or use the on-screen number pad.
- 3Press Enter or tap Submit to confirm your answer.
- 4Correct answers add time; wrong answers deduct time.
- 5Keep going until the clock hits zero.
⌨️Controls
| Action | 💻 Desktop | 📱 Mobile |
|---|---|---|
| Select answer | Click or press 1–4 | Tap answer button |
📋Rules
- ▸Each correct answer awards +5 seconds to the timer.
- ▸Each wrong answer deducts 3 seconds.
- ▸Difficulty increases every 10 correct answers.
- ▸Operations include addition, subtraction, multiplication, and division.
- ▸Division results are always whole numbers — no fractions.
💡Pro Tips
- ★Look for shortcuts: 9 × n = (10 × n) − n is faster than direct multiplication.
- ★Subtraction from round numbers is easiest — use 100 or 1000 as anchors.
- ★Don't second-guess easy questions; hesitation costs more time than a wrong answer.
- ★Practice your multiplication tables for 6, 7, 8 — they appear most often.
ℹ️About
CalcRush is a high-intensity mental arithmetic trainer designed to sharpen your number skills under pressure. A randomised problem appears on screen — addition, subtraction, multiplication, or division — and you must answer before the clock reaches zero. Get it right and earn five extra seconds; get it wrong and lose three. The difficulty curve is automatic: every ten correct answers the numbers get bigger, the operations get trickier, and your time buffer shrinks. Whether you are a student drilling multiplication tables before an exam, a professional keeping your mental arithmetic sharp, or simply someone who loves beating their own high score, CalcRush adapts to your current level and keeps pushing. All division answers are whole numbers, so no mental gymnastics with fractions — pure speed is the challenge. Free to play on desktop and mobile, with no sign-up or download required.