About this calculator

Useful for sizing pumps, taps and irrigation. 1 US GPM = 3.78541 L/min. UK GPM uses imperial gallons (4.54609 L).

Frequently asked questions

What does the Flow Rate Calculator do?

Convert between L/min, L/s, GPM (US) and GPM (UK) instantly. Useful for sizing pumps, taps and irrigation. 1 US GPM = 3.78541 L/min. UK GPM uses imperial gallons (4.54609 L).

Is the Flow Rate Calculator free to use?

Yes. Every calculator on Calcurly.com is free, works in your browser without sign-up, and can be embedded on your own website.

How accurate is the Flow Rate Calculator?

Results are calculated in real time using industry-standard formulas. Treat the output as a well-informed estimate — always cross-check with local regulations, product datasheets, or a qualified plumbing professional before committing to a purchase or a job.

What inputs does the Flow Rate Calculator need?

Enter values for: Flow, Unit. Sensible defaults are pre-filled where possible so you can start with a single change.

Can I embed the Flow Rate Calculator on my own website?

Yes — copy the iframe snippet at the bottom of this page, or use the Embed Generator to customise the size. The embedded version stays in sync with the live calculator on Calcurly.com.