Inputs have a context
Check the units and the intended use of the calculation. A preliminary estimate is most useful when its assumptions match the question you are asking.

RIDA TEC / TOOLS
Explore twelve engineering calculators with visible formulas, units and assumptions. Use them to understand the relationships before moving into detailed design.
Explore the detailsL/s = m³/h ÷ 3.6
Volumetric flow; output in litres per second.
Preliminary calculations support understanding. Engineering decisions require site data and qualified review.

Check the units and the intended use of the calculation. A preliminary estimate is most useful when its assumptions match the question you are asking.
Use the displayed formula to understand how a change in input affects the result. Detailed equipment selection still needs application-specific information and engineering review.
R / READ THE RESULT
Make the input unit match the field label before comparing results.
The formula describes a model. Understand its stated limits before using the estimate.
Detailed equipment selection needs the actual operating conditions and a suitable engineering review.