Elevation Gain Calculator
Calculate elevation gain, slope grade percentage, and trail difficulty rating for any hiking route or road segment. Enter start and end elevations plus horizontal distance to get instant results.
About this calculator
Elevation gain is simply the difference between ending and starting elevation: gain = endElevation − startElevation. A negative result indicates a net descent. Slope grade expresses steepness as a percentage: grade (%) = (gain / horizontal distance in meters) × 100. Since horizontal distance is entered in kilometers, it is converted first: distanceM = distance × 1,000. The absolute value of grade is used for difficulty rating, which scales from 1 (easy, grade < 5%) to 5 (very hard, grade ≥ 20%). These thresholds are commonly used in trail classification and cycling route grading. A 10% grade means you rise 10 meters for every 100 meters traveled horizontally.
How to use
Imagine a trail starting at 800 m elevation and ending at 1,400 m, with a horizontal distance of 6 km. Gain = 1,400 − 800 = 600 m. Convert distance: 6 km × 1,000 = 6,000 m. Grade = (600 / 6,000) × 100 = 10%. Since 10% falls in the range [10, 15), the difficulty rating is 3 out of 5 — moderate to hard. If you reversed the route (descent), gain = −600 m and the grade is still 10% in absolute terms, giving the same difficulty rating.
Frequently asked questions
What is a good elevation gain per kilometer for hiking trails?
A gain of 50–100 m per kilometer (5–10% grade) is considered moderate and suitable for most recreational hikers. Below 50 m/km is gentle and accessible to beginners, while above 150 m/km (15% grade) is steep and demands strong fitness and proper footwear. Elite mountain routes can exceed 300 m/km on technical sections. When planning a hike, total elevation gain matters as much as grade — a long trail at moderate grade can be more exhausting than a short steep one.
How does grade percentage differ from slope angle in degrees?
Grade percentage and slope angle both describe steepness but on different scales. A 100% grade means you rise 1 meter for every 1 meter of horizontal distance, which equals a 45-degree angle. A 10% grade corresponds to about 5.7 degrees. The relationship is: angle = arctan(grade / 100). Grade percentage is preferred in road engineering, cycling, and hiking because it is easier to visualize and measure with simple instruments, while degrees are more common in geometry and trigonometry contexts.
Why does elevation gain matter for estimating hiking time?
Elevation gain significantly increases the energy and time required for a hike beyond what flat distance alone would suggest. Naismith's Rule, a classic hiking estimation method, adds 1 hour for every 600 meters of ascent on top of the base pace. A 10 km flat hike might take 2.5 hours, but the same distance with 600 m of gain could take 3.5 hours or more. Underestimating elevation gain is one of the most common causes of hikers running out of daylight, so it is a critical factor in any route plan.