Why eDPI exists, and its one limitation
Two players can report completely different DPI and sensitivity values and still have identical setups. eDPI collapses the pair into one number — 800 × 1.0 and 400 × 2.0 both give 800 eDPI — which makes comparisons quick. The catch: eDPI is only meaningful inside one game, because each game converts counts to rotation at a different rate.
cm/360: the physical number
cm/360 answers a simpler question: how far must the mouse move to turn a full circle? It is physical distance, so it is comparable across games as long as each game's yaw constant is known. This is the number aim trainers use and the one that survives a change of mouse, DPI step or game — which is why it is the basis of the sensitivity converter on this site.
Typical ranges, and why they differ
Tactical shooters reward precision at a distance and punish over-turning, so players cluster around 25–50 cm/360. Tracking-heavy games and those with fast movement and vertical fights run faster, typically 15–25 cm/360. These are conventions, not rules: what matters is that the number is stable for you, so your hand keeps the same reference whether you are playing at home or on a tournament machine.
Using these numbers in practice
To copy a pro's setup, convert their DPI and sensitivity into cm/360 and then compute the sensitivity your own mouse needs to match it. To switch games without losing aim, use the converter and keep the cm/360 identical. To change DPI, adjust sensitivity in the opposite direction and verify with the calculator — if cm/360 is unchanged, the feel is unchanged.