Elevation gain & grade calculator
How steep is it? Enter a distance and the height gained to get the grade in percent, degrees and as a ratio, or drop in a GPX file to find the steepest climbs and descents on the whole route.
20.0%grade
11.3°angle
1 in 5ratio
Steep
Slow, deliberate walking; many people stop for breath.
- Map (horizontal) distance
- 1.50 km
- Length along the slope
- 1.53 km
- Tobler walking speed here
- 2.5 km/h
- Naismith time for this stretch
- 48 min
From your GPX file
Point at the profile to read the distance, height and local grade.
| Grade | Uphill | Downhill |
|---|
Percent, degrees and ratio
Grade is the height gained divided by the horizontal distance: 100 m up over 1 km of map distance is 10%. The angle is the arctangent of that ratio, so 10% is about 5.7°, and 100% is 45°, not vertical. A ratio of "1 in 10" means one unit up for every ten along, which is the same 10%.
| Grade | Angle | Ratio | On foot |
|---|---|---|---|
| 5% | 2.9° | 1 in 20 | gentle |
| 10% | 5.7° | 1 in 10 | moderate |
| 20% | 11.3° | 1 in 5 | steep |
| 30% | 16.7° | 1 in 3.3 | very steep |
| 50% | 26.6° | 1 in 2 | hands often needed |
Map distance or trail distance?
Distances measured on a map, or from coordinates in a GPX file, are horizontal. A wheel or a step count along the trail measures the longer slope length. Choose which one you have and we correct for it. On ordinary trails the difference is small: about 2% at a 20% grade.
Reading a GPX file
We resample the track every few metres, smooth the heights over about 100 m, and ignore changes smaller than 2 m, so GPS jitter does not count as climbing. The steepest sections are measured over 100 m, 500 m and 1 km of horizontal distance, which says more about how a climb feels than the single worst point.
Questions
Is a 100% grade vertical?
No. 100% means the rise equals the run, which is a 45° slope. A vertical wall has no finite grade.
Why is my total ascent lower than my watch says?
Watches and apps often count every small rise. We smooth the profile and ignore changes under 2 m, which gives a steadier total for planning.
Does the grade change my walking time?
Yes, in different ways for each rule. Naismith adds an hour per 600 m of climb whatever the grade; Tobler's speed falls steadily as the grade rises. The hiking time calculator shows both.