Grade Percent Calculator
Convert angle degrees to grade percentage for running, hiking, and cycling.
Grade Percent Formula
Grade % = tan(angle in degrees) × 100
Grade % = (rise ÷ run) × 100
Angle = arctan(grade/100) in degrees
Grade Difficulty Reference
| Grade % | Angle | Difficulty | Example |
|---|---|---|---|
| 0–3% | 0–1.7° | Flat | Road running |
| 3–6% | 1.7–3.4° | Gentle hill | Easy climb |
| 6–10% | 3.4–5.7° | Moderate climb | Most road races |
| 10–15% | 5.7–8.5° | Steep | Challenging climb |
| 15–20% | 8.5–11.3° | Very steep | Walking pace |
| >20% | >11.3° | Extreme | Scrambling / hiking |
Frequently Asked Questions
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Grade percentage is the ratio of vertical rise to horizontal distance, expressed as a percent. Grade % = (rise ÷ run) × 100. A 10% grade means 10 meters up for every 100 meters forward.
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Grade % = tan(degrees) × 100. For example, 5 degrees = tan(5°) × 100 ≈ 8.75% grade. Most running/hiking grades are 3–15 degrees (5–27% grade).
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Angle is measured in degrees from horizontal. Grade is the vertical/horizontal ratio (as %). Grade is more practical for running/cycling; angle is more common in construction/engineering.
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0–5% = flat, 5–10% = moderate hill, 10–15% = steep, 15%+ = very steep. Most road races stay below 10%. Trail runners encounter 15–30% regularly.
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On steep hills, pace slows significantly. A 10% grade might slow you 30–50% depending on fitness. Elite runners handle hills better; beginners slow more. Downhill offers pace gains.
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Most runners can sustain 5–8% grade for extended periods. Above 10%, most switch to walk-run. Steep grades (15%+) require power and muscular endurance, not just aerobic capacity.
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Cyclists face steeper grades than runners (5–15% common on road climbs, 15%+ on mountain bike trails). Grade determines gearing, pacing, and recovery needs.
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A null or flat grade is 0%. Any grade > 0 is uphill; < 0 is downhill. On treadmills, 0% grade feels harder than true flat (rolling resistance), so 1–2% mimics outdoor flat running.
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No. Grade is the steepness over a set distance. Elevation gain is total vertical rise. A 5-mile climb with 2000 ft elevation gain has an average grade of (2000 ÷ 26400) × 100 ≈ 7.6%.
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If GPS records elevation (meters) and horizontal distance (meters): Grade % = (Δelevation ÷ horizontal distance) × 100. Most running apps estimate this automatically.
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A ramp is continuous slope (measured as grade %). Stairs are discrete steps. Stairs impose higher effort per unit elevation due to impact and balance requirements.
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Running: 5–10% typical, 15%+ rare. Cycling: 8–12% road, 15%+ off-road. Skiing: 15–40% typical. Steepness perception varies by sport due to friction, gearing, and technique.