1. What is Percent Grade?

Percent grade is a way to express the steepness of a slope as a percentage. It represents the ratio of vertical change to horizontal distance multiplied by 100. It's commonly used in road construction, hiking trails, and engineering projects.

2. How Does the Calculator Work?

The calculator uses the percent grade formula:

Where:

• \( \text{vertical\_change} \) — Height difference (feet)
• \( \text{horizontal\_distance} \) — Horizontal distance (feet)

Explanation: The formula calculates what percentage of the horizontal distance is accounted for by the vertical change.

3. Importance of Percent Grade Calculation

Details: Percent grade is crucial for determining slope steepness in construction, transportation planning, and outdoor activities. It helps assess accessibility and safety of slopes.

4. Using the Calculator

Tips: Enter vertical change and horizontal distance in feet. Both values must be positive numbers. The calculator will output the slope as a percentage.

5. Frequently Asked Questions (FAQ)

Q1: What does a 10% grade mean?
A: A 10% grade means the elevation changes 10 feet for every 100 feet of horizontal distance.

Q2: How does percent grade relate to degrees?
A: Percent grade is different from angle in degrees. A 45° angle equals a 100% grade (1:1 slope).

Q3: What's the maximum grade for highways?
A: In the US, interstate highways typically have maximum grades of 6% in mountainous areas.

Q4: How steep is too steep for walking?
A: Most people find slopes above 15-20% challenging to walk up for extended periods.

Q5: Can percent grade be negative?
A: Yes, negative percent grade indicates a downward slope when moving from left to right.