1. What is Slope Percentage?

Slope percentage represents the steepness of a slope expressed as a percentage. It is calculated as the ratio of vertical rise to horizontal run multiplied by 100. This measurement is widely used in construction, engineering, and landscaping.

2. How Does the Calculator Work?

The calculator uses the slope percentage formula:

Where:

• \( Rise \) — Vertical height difference
• \( Run \) — Horizontal distance
• \( Slope \% \) — Slope expressed as percentage

Explanation: For every unit of horizontal distance, the slope percentage indicates how many units the surface rises or falls vertically.

3. Importance of Slope Calculation

Details: Accurate slope calculation is essential for proper drainage design, road construction, ramp accessibility compliance, roof pitch determination, and landscape grading.

4. Using the Calculator

Tips: Enter rise and run values in the same units (feet, meters, inches, etc.). Both values must be positive numbers greater than zero for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What is a common slope ratio example?
A: A 1:12 slope ratio equals 8.33% slope, which is the maximum slope for wheelchair ramps according to ADA standards.

Q2: How do I convert slope percentage to degrees?
A: Use the formula: degrees = arctan(slope percentage ÷ 100). For example, 100% slope = 45 degrees.

Q3: What is considered a steep slope?
A: Generally, slopes above 25% are considered steep, while slopes above 40% are very steep and may require special construction considerations.

Q4: Can slope percentage be negative?
A: In calculation, slope percentage is always positive. Negative values typically indicate downward slope direction in context.

Q5: What units should I use for rise and run?
A: Use any consistent units (feet, meters, inches), as the ratio eliminates unit dependency in the final percentage result.