Questions

Every measurement traces to a linked source table — either a test-bench run or a manufacturer datasheet — and values are transcribed verbatim. Nothing is extrapolated, smoothed, or estimated. Each run records its source URL and a verification date, and you can see the lot on the data sources page. The full dataset is also downloadable as CSV.

Start from the weight you need to lift, not the motor. Work out hover thrust for your all-up weight, then pick a motor whose measured curve crosses that number well below 100% throttle — you want headroom for wind, altitude, and a battery that sags under load. The calculator interpolates between the measured points for you, and the motor rankings let you sort by measured max thrust, peak current, or efficiency at 50% throttle.

No. It interpolates strictly between published measurements and will not extend a curve past its last measured point. If a thrust you need falls outside the measured range, the tool tells you rather than inventing a number.

KV is a no-load constant (revolutions per volt) and says nothing about thrust. Two motors with identical KV can differ substantially in efficiency and winding once they are actually loaded. That is why everything here comes from measured thrust and current at real throttle steps rather than from the KV figure.

Grams per watt, at each measured throttle step: thrust divided by voltage times current. It is shown on every point of the measurement tables, because efficiency is usually the number that decides a build — and it varies far more across the throttle range than the headline figure suggests.

It is a model, not a quote. It accounts for filament mass and price, machine power draw and electricity rate, hardware depreciation and nozzle replacement, operator time, and a contingency buffer — but it cannot know your specific machine's real-world behaviour, and it will not know about a failed print. Treat the output as a defensible starting point for a conversation, not as an invoice.

PLA for anything that does not need heat or impact resistance, PETG as the general-purpose upgrade, ABS/ASA for heat-exposed parts, and TPU for anything flexible. The print cost engine carries the measured density and price for the common ones, so you can compare material cost against each other before deciding.

Yes, and it is the only way the dataset grows. Both tools have a contribution form that queues a submission for review. Nothing submitted goes live automatically — it lands unpublished, and is only published after it has been read and checked against its source.

Because that is what the data says. A propeller's behaviour depends heavily on the motor it is mounted on — matching, load, and the resulting operating point — so each motor/prop pair is a separate measurement with its own source. Every propeller page lists every motor it was actually tested on.