Three numbers from one sample
The tool asks for a before percentage, an after percentage and the minutes between them. From those it derives everything else with plain arithmetic — no hidden game data.
- Observed pace = (after − before) ÷ minutes sampled. A run that moved 40% to 55% in five minutes is clearing 3% per minute.
- Estimated finish = remaining progress ÷ observed pace. At 3% per minute, the 45% left to clean takes 15 minutes.
- Required rate = remaining progress ÷ minutes left on the in-game timer. If only 12 minutes remain, you need 3.75% per minute — 0.75 more than you are producing.
That gap between observed and required rate is the whole decision. When the gap is small, keep cleaning and re-sample after the next area opens. When it is large, the timer will not wait for hand-cleaning: the community walkthrough (checked 2026-10-06) says the documented speed jumps are the Leaf Blower with Vents activated and, in the Basement, the Molotov pile-and-burn method.