How we score slopes and resorts
Every number on this site is computed from the actual mapped geometry of the mountain — the same OpenStreetMap-derived data that powers the offline maps in the Bonvo app. No brochure claims, no self-reported piste kilometers. That means our numbers are sometimes smaller than the resort's own — and that's the point.
The Bonvo Slope Score (0–100)
Each run is scored out of 100 from four measured components:
Vertical drop
Measured from the run's elevation profile. Full marks at 900 m of drop — a genuine top-to-bottom mountain descent.
Length
Measured along the actual line of the run, not the map's straight-line distance. Full marks at 5 km.
Gradient character
How well the run's average gradient fits its difficulty class. A green run is judged as a green run (ideal 5–18%), a black as a black (22–48%) — so a perfectly pitched beginner run scores as well as a perfectly pitched expert one. Runs that are mislabeled or oddly flat/steep for their color lose points.
Flow
Flat stretches and uphill sections break a descent's rhythm (and force snowboarders to unstrap). We detect them in the elevation profile and subtract points for each.
Grades: 85+ world-class, 70+ outstanding, 55+ excellent, 40+ very good, 25+ enjoyable. The same profile analysis powers each run's snowboard-friendliness verdict.
The Bonvo Resort Score (0–100)
Terrain size
Total measured kilometers of marked downhill runs. Full marks at 150 km.
Vertical
Lift-served vertical from the highest to the lowest marked point. Full marks at 1,500 m.
Variety
How evenly the terrain spreads across green, blue, red and black — a mountain for every day and everyone in the group.
Lift network
Number of lifts, with extra weight for high-capacity gondolas, cable cars and funiculars.
Extras
Snow parks, floodlit night skiing, nordic trails, and how completely the resort's runs are named and mapped.
Where the data comes from
Run and lift geometry is derived from OpenStreetMap (© OpenStreetMap contributors, ODbL) enriched with elevation data, extracted and processed by Bonvo. Because bounding areas of neighbouring resorts can overlap, we spatially filter every run to the resort's own published boundary before computing statistics. Data is refreshed as the underlying maps improve — if you spot an error, the fastest fix is often to improve the map on OpenStreetMap itself.
All of this analysis ships inside the free app — offline.
Download the resort once in Bonvo Ski Maps and every run, lift and your friends' live positions keep working in airplane mode. Free this season.
See the scores in action: the 100 best ski resorts, ranked or browse the full resort directory.