---
title: "Trail Grade & Elevation Gain Calculator | Summit Cabin"
description: "Work out percent grade, slope angle and 1-in-N ratio from distance and height gain, convert between them, or analyse the climbs in a GPX track."
url: https://summitcabin.top/elevation-gain-grade/
---

# 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 5 ratio

Steep

Slow, deliberate walking; many people stop for breath.

[Turn distance and climb into walking time](https://summitcabin.top/)

## 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.

Downloading a GPX file from a route site that wants your email address first? A free disposable inbox from [CleanTempMail](https://cleantempmail.com/) receives the link without handing over your own address.

## 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.