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Slope Percentage Formula:
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Slope percentage is a way to express the steepness of a slope as a percentage. It represents the vertical rise divided by horizontal run, multiplied by 100. This measurement is commonly used in civil engineering, construction, and landscaping to describe incline gradients.
The calculator uses the trigonometric formula:
Where:
Explanation: The tangent of an angle in a right triangle equals the ratio of the opposite side (rise) to the adjacent side (run). Multiplying by 100 converts this ratio to a percentage.
Details: Accurate slope percentage calculation is essential for proper drainage design, road construction, wheelchair ramp compliance, roof pitch determination, and ensuring structural stability in various engineering and construction projects.
Tips: Enter the slope angle in degrees (0-90°). The calculator will automatically compute the corresponding slope percentage. Common examples: 45° = 100% slope, 30° ≈ 57.7% slope, 15° ≈ 26.8% slope.
Q1: What's the difference between slope degrees and slope percentage?
A: Degrees measure the angle of inclination, while percentage expresses the vertical rise per 100 units of horizontal distance.
Q2: What is considered a steep slope?
A: Generally, slopes above 25% (about 14°) are considered steep, while slopes above 50% (about 26.6°) are very steep and may require special engineering considerations.
Q3: How is slope percentage used in construction?
A: It's used for road gradients, drainage systems, ramp design, roof pitches, and ensuring ADA compliance for accessibility.
Q4: Can I convert slope percentage back to degrees?
A: Yes, use the formula: degrees = arctan(slope%/100). Most scientific calculators have an inverse tangent function for this conversion.
Q5: What are common slope percentages for different applications?
A: Driveways: 12-15%, ADA ramps: ≤8.33%, Roofs: 20-40%, Drainage pipes: 1-2%, Hiking trails: ≤15% for comfortable walking.