Unit conversions
Convert between metric units — length (mm/cm/m/km), mass (g/kg), capacity (ml/l). Convert hours, minutes, seconds.
Available exercises
Length: convert down
Convert from a larger unit to a smaller one (km → m → cm → mm).
Length: convert up
Convert from a smaller unit to a larger one (mm → cm → m → km).
Length: fill the missing unit
Fill the missing number when units are converted (e.g. 1 m = ? cm).
Imperial length: compare
Compare imperial length quantities expressed in different units.
Imperial length: convert down
Convert miles → yards → feet → inches.
Imperial length: convert up
Convert inches → feet → yards → miles.
Read the clock — to any minute
Read analogue and digital clocks to the exact minute.
Time: convert units
Convert between seconds, minutes, hours, days and weeks.
Elapsed time problems
Work out how much time has passed between two clock times.
Capacity: convert millilitres and litres
Convert between millilitres, decilitres, litres and hectolitres.
Mass: convert grams and kilograms
Convert between grams, kilograms and tonnes.