Measurement and Units
Length, weight, liquids and time. Every question is a conversion, and every conversion comes down to one question you can always ask yourself.
No account, and the maths stays in your browser — more— less
This activity is for learning and practice. Anything it suggests is indicative only — it is not a formal assessment and not a substitute for a teacher or tutor.
Nothing you answer is sent to Zerdly. Progress is saved on this device only if you switch saving on, and you can delete it at any time. How Kids Maths handles data.
Set your country and age — change
Setting an age keeps the questions at the right level for that age. It does not lock anything — you can still try any topic, at any age, in any order. Levels are a guide only, not a curriculum.
Your age is not saved anywhere. Your country is remembered only if you have switched saving on.
Saving your progress
Nothing is being saved. You can practise as much as you like — when you close the tab, the session is gone.
The one question that settles every conversion
Which of the two units is bigger? That is it. If you are swapping to a smaller unit you will need more of them, so the number gets bigger. Swapping to a bigger unit, you need fewer, so the number gets smaller.
A metre is bigger than a centimetre, so 3 m becomes the larger number 300 cm. Going the other way, 300 cm becomes the smaller number 3 m. If your answer moved the wrong way, that is the check that catches it — before you have even thought about how many zeros.
Time is the one that breaks the trick
Metric units all go up in tens, so people learn to just move the decimal point. Time does not play along: there are 60 seconds in a minute and 60 minutes in an hour. The bigger-or-smaller question still works perfectly, which is exactly why it is worth learning instead of the shortcut.
School levels
School levels are a guide only. They show where a skill is usually taught in each country and are not taken from, aligned to, or endorsed by any curriculum authority. Your school may cover it earlier or later.