1. What is a Slope Ratio To Percentage Calculator?

Definition: This calculator converts a slope ratio (run:rise) to a percentage grade.

Purpose: It helps engineers, landscapers, and construction professionals convert between different slope measurement systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( \% \) — Slope percentage
• \( R \) — Slope ratio (run/rise)

Explanation: The inverse of the ratio is multiplied by 100 to convert it to a percentage grade.

3. Importance of Slope Conversion

Details: Different industries use different slope measurements. Converting between them ensures proper communication and compliance with regulations.

4. Using the Calculator

Tips: Enter the slope ratio (run divided by rise). For example, for a 4:1 slope, enter 4. The value must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between ratio and percentage slope?
A: Ratio is run:rise (e.g., 4:1), while percentage is rise/run × 100 (e.g., 25% for 4:1).

Q2: How do I measure the ratio?
A: Measure horizontal distance (run) and vertical drop (rise) over the same units, then divide run by rise.

Q3: What's a common slope ratio for roads?
A: Typically 2% (50:1 ratio) for highways, up to 6% (16.67:1) for steep roads.

Q4: How does this relate to angle in degrees?
A: Percentage = tan(angle) × 100. This calculator focuses on ratio to percentage conversion.

Q5: What's the maximum slope for ADA compliance?
A: 1:12 ratio (8.33%) is the maximum for wheelchair ramps under ADA guidelines.