Subtraction speed test
Subtraction is where most people slow down: borrowing is awkward to do in your head. The fix is to stop borrowing.
Quick test: 20 subtraction problems. Answers advance automatically.
The test
R3CK0N's subtraction drill always puts the larger number first, so answers are never negative. Easy uses numbers from 2 to 99, Medium 10 to 999, and Hard 100 to 9,999. Run it against a timer or over a fixed count and get your problems per minute and accuracy.
Method 1: compensation
Round the number you're subtracting to something friendly, subtract that, then give back the difference.
742 − 398 = 742 − 400 + 2 = 344Method 2: count up
When the two numbers are close, or the top one is a round number with zeros, count up from the smaller one instead — the way a cashier gives change.
5,003 − 2,868 2,868 → 3,000 is 132 3,000 → 5,003 is 2,003 132 + 2,003 = 2,135Method 3: complements from a power of ten
To subtract from 100, 1,000 or 10,000, take each digit from 9 — except the last, which you take from 10.
1,000 − 367 → (9−3)(9−6)(10−7) → 633 1,000 − 742 → (9−7)(9−4)(10−2) → 258No borrowing at all. It's the fastest way to work out change, and it's the building block for the other two methods.
Which to use
| If… | Use |
|---|---|
| the number being subtracted ends in 7, 8 or 9 | Compensation |
| the numbers are close together, or the top one is round | Count up |
| you're subtracting from 100, 1,000 or 10,000 | Complements |
Frequently asked questions
Is it free?
Yes — no ads, no paywall, and no account needed. Results stay in your browser unless you sign in to sync them.
Can I track my progress?
Every run is saved, and the Stats tab charts your speed and accuracy over time for each operation and difficulty.
Start the subtraction test