Rainfall calculator, metric units
How much water falls during a storm?

Note: You can enter numbers into any or all of the boxes below:

Method A: Use METERS (for areas such as your roof or yard).

Method B: Use SQUARE KILOMETERS (for large areas).

Select one or more methods to choose the size of your area:

Method A: Meters

by

Method B: Square Kilometers

Select a rainfall amount:

Rates of rainfall:

Drizzle, very small droplets.
Slight (fine) drizzle: Detectable as droplets only on the face, car windscreens and windows.
Moderate drizzle: Windows and other surfaces stream with water.
Heavy (thick) drizzle: Impairs visibility and is measurable in a raingauge, rates up to 1 mm per hour.
Rain, drops of appreciable size and may be described as small to large drops. It is possible to have rain drops within drizzle!
Slight rain: Less than 0.5 mm per hour.
Moderate rain: Greater than 0.5 mm per hour, but less than 4.0 mm per hour.
Heavy rain: Greater than 4 mm per hour, but less than 8 mm per hour.
Very heavy rain: Greater than 8 mm per hour.
Slight shower: Less than 2 mm per hour.
Moderate shower: Greater than 2 mm, but less than 10 mm per hour.
Heavy shower: Greater than 10 mm per hour, but less than 50 mm per hour.
Violent shower: Greater than 50 mm per hour.