Record what you actually know
Separate counted teeth and drawing dimensions from assumed efficiencies. If speed or torque is a nameplate value, record the load condition it describes. The CSV output makes the sequence of ratios and resulting values inspectable by another person.
Check conservation consistently
For a reduction, ideal speed decreases while torque increases. With efficiency below one, output power must not exceed input power. A surprisingly large result often comes from reversing driver and driven teeth or mixing a compound train with an idler arrangement.
Review strength independently
Kinematic calculations do not determine tooth stress, shaft deflection, bearing loads, belt tension or guarding. Use the applicable component guidance for those checks. Re-run the saved calculation if the physical design or supplier component dimensions change.
Assemble a calculation packet
Keep the entered stage rows or pulley dimensions with the CSV and SVG downloads. State which shaft is the input, the units, the efficiency assumption and the source of each dimension. A row saying 20 to 60 teeth is much less ambiguous when a sketch identifies the two gears and the shaft connection to the next stage.
For the default two-stage example, 10 N·m at 1,500 rpm corresponds to about 1,571 W. Multiplying by 0.9409 overall efficiency gives about 1,478 W at the output. Recombining the calculated output torque and speed should reproduce that value within rounding. This is an arithmetic consistency check, not a measurement of the physical drive.
Make revisions traceable
If a supplier changes pulley pitch diameter or a gearbox stage is substituted, re-run the affected calculation rather than editing a result label. Compare both intermediate and final values. The diagram is a communication aid; it does not contain shaft fits, tooth geometry, material specification or a manufacturing drawing. Keep those design records alongside the calculation instead of treating the exported SVG as a complete mechanical specification.