Time Lab
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Time Math Attack

Add, subtract and convert time against the clock

Score0
Best0
Level1
Streak0
Accuracy—

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Features

➕Add minutes, then whole hours and minutes with carries — the everyday base-60 arithmetic that trips people up because 60 minutes, not 100, make an hour.
🌗Higher levels switch to 24-hour time and subtraction, so you have to add and take away across midnight without losing the day.
🌐From level 4, convert between real time zones — Delhi, London, New York, Tokyo and more — including the half-hour and 45-minute offsets that catch everyone out.
🔥A burning fuse limits every answer and shortens as you climb the levels. Faster answers score more, streaks multiply, and three wrong carries end the run.

Frequently Asked Questions

How do you add and subtract time?

Work in base 60: add the minutes, and every time they pass 60 carry one hour and subtract 60 from the minutes. Subtraction borrows the other way — take an hour and add 60 minutes. The mistake most people make is treating minutes like decimals, so 1:45 + 30 min becomes 2:15, not 1:75.

What is a carry in time math?

A carry is when the minutes add up to 60 or more and roll into the next hour — like 40 + 35 = 75 minutes = 1 hour 15. Crossing 12 or 24 rolls into AM/PM or the next day. The game deliberately picks numbers that force these carries so you practise the tricky part.

How do time-zone questions work?

Each city has a fixed UTC offset, so converting means adding the difference between the two offsets. London to Delhi is +5.5 hours, for example. The half-hour offsets (India, +5:30) and the rare 45-minute one (Nepal, +5:45) are the classic traps, and they only appear at higher levels.

Why practise time math?

Adding and subtracting time comes up constantly — arrival times, meeting across zones, cooking, shift work — and base-60 arithmetic is genuinely error-prone. A quick timed drill sharpens the mental shortcuts so you do it faster and more reliably in real life.