Water Calculators
Plan tank size, daily usage, refills, grey water and pump flow.
Free water calculators for van life water system
Quick, accurate tools to help you plan, size and budget the water side of your van conversion. Pick a calculator below to get started.
Tank size
Find the fresh water tank size for your trip length.
Open
Daily water use
Estimate litres per day from drinking, cooking, washing and showers.
Open
Days remaining
How many days of water you have left at current usage.
Open
Grey water fill
When the grey tank fills up given your usage and tank size.
Open
Pump flow
Convert pump LPM/GPM and estimate fill times.
Open
Why van life water system planning matters
Avoid costly mistakes
Sizing your water correctly up front saves money, weight and time. Use these calculators before you buy components or commit to a layout.
Built for van life
Every formula is tuned for real campervan and motorhome use cases, with sensible defaults so you can get a useful answer in seconds.