Slope Degrees to Percent Calculator

Last updated: 28 Oct 2025 | Author: Brij | Review By: Irshad

Share on :

Easily convert slope degrees to slope percentages using this Slope Degrees to Percent Calculator. Perfect for engineers, landscapers, and architects—includes formulas, examples, and conversion tables.

Slope Angle:

Enter angle in degrees (0° to 90°)

Common Slope Angles:

Slope Conversion Results

Slope Percentage:

Slope Ratio:

H:V

Rise per 100 units:

units

Vertical rise per 100 horizontal units

Slope Grade:

Moderate slope

The Slope Degrees to Percent Calculator helps you easily convert slope angles (in degrees) into slope percentages and ratios. This conversion is essential in construction, landscaping, road design, and accessibility projects, where slopes are often expressed as percentages rather than degrees.

How to Calculate Slope Percentage from Degrees

The slope percentage expresses how much a surface rises vertically compared to its horizontal distance.

The formula to convert degrees to percentage is:

$\text{Slope Percentage} = \tan(\text{Slope Angle}) \times 100$

Formula to Convert Slope Degrees to Ratio

The slope ratio is another way to represent slope steepness, showing the horizontal distance for every unit of vertical rise.

The formula is:

$\text{Slope Ratio} = 1 : \left( \frac{1}{\tan(\text{Slope Angle})} \right)$

Example 1

Let’s say your slope angle is 10°.

$\text{Slope Percentage} = \tan(10°) \times 100 = 0.1763 \times 100 = 17.63\%$

Slope Ratio:

$\text{Slope Ratio} = 1 : \left( \frac{1}{\tan(10°)} \right) = 1 : 5.67$

Example 2

For a slope angle of 20°:

$\text{Slope Percentage} = \tan(20°) \times 100 = 0.3640 \times 100 = 36.4\%$

Slope Ratio:

$\text{Slope Ratio} = 1 : \left( \frac{1}{\tan(20°)} \right) = 1 : 2.75$

Example 3

For a steep slope angle of 30°:

$\text{Slope Percentage} = \tan(30°) \times 100 = 0.5773 \times 100 = 57.73\%$

Slope Ratio:

$\text{Slope Ratio} = 1 : \left( \frac{1}{\tan(30°)} \right) = 1 : 1.73$

FAQs

1. What is a slope percentage?

A slope percentage shows how much a surface rises vertically compared to its horizontal distance, expressed as a percent.

2. How do I convert degrees to slope percentage?

Use the formula:

$\text{Slope Percentage} = \tan(\text{Slope Angle}) \times 100$

3. What is the difference between slope percent and slope ratio?

Slope percent is expressed as a percentage, while slope ratio expresses the same slope as a proportion like “1:5”.

4. What is a 45° slope in percent?

A 45° slope equals 100%, meaning the rise equals the run.

5. Why is slope conversion important?

It ensures accurate design in ramps, roads, and roofs by maintaining safety and functionality standards.

6. Can I use this calculator for wheelchair ramps or driveways?

Yes, it’s commonly used for accessibility design, landscaping, and structural engineering.

Check out 22 Similar Calculators:

Help Improve This Calculator

Your suggestions help us make better tools for everyone.