RideBriefing › Climb categories, from Cat 4 to HC
Guide · Climbs
Climb categories, from Cat 4 to HC
Climb categories come from professional racing: the Tour de France labels its climbs from category 4, the easiest, to hors catégorie (HC), "beyond category". Many cycling apps use the same idea to rate any climb on any route. RideBriefing finds and categorises every climb in your GPX file.
How a climb is categorised
The category comes from a simple score: the climb's length in metres multiplied by its average gradient in percent. A longer or steeper climb gets a higher score.
| Category | Score from | Example |
|---|---|---|
| Cat 4 | 8,000 | 2 km at 4% |
| Cat 3 | 16,000 | 3 km at 5.5% |
| Cat 2 | 32,000 | 5 km at 6.5% |
| Cat 1 | 64,000 | 8.8 km at 7.5% (Col de la Forclaz, from Lake Annecy) |
| HC | 80,000 | 21 km at 7.5% (Mont Ventoux, from Bédoin) |
Shorter rises below 8,000 are listed as uncategorised. Real race organisers also weigh in the position of a climb in the stage and the road surface, so a climb's official category in a race can differ from its score.
What RideBriefing shows for each climb
- Length, average and maximum gradient: the maximum is the steepest 200 m, so a single steep corner doesn't distort it.
- Elevation gain and summit height.
- The gradient for every kilometre, in a coloured profile like a race book, so you know where the hard part is.
- When you'll reach the foot and the top, and how long it takes at your speed.
- The name of the pass, from OpenStreetMap, when the climb leads to a named col or saddle.
How climbs are found
RideBriefing smooths the elevation of your route, then looks for rises that keep going up, allowing short dips along the way. Flat run-ins at the start and end are trimmed, so the reported gradient is the gradient you'll actually ride. A climb needs at least 400 m, 25 m of gain and a 3% average to be listed.
See the climbs on your next route.
Brief your rideQuestions
Why is my climb's length different from another app?
Apps use different elevation data and decide differently where a climb starts and ends. RideBriefing trims flat sections at both ends, which usually gives a slightly shorter, steeper climb than the full road section.
What does HC mean?
Hors catégorie, French for "beyond category": the longest and hardest climbs, such as Mont Ventoux, the Stelvio or Alpe d'Huez.
How is the maximum gradient measured?
Over the steepest 200 m of the climb. Shorter spikes are usually noise in the elevation data rather than real ramps.