Welcome to our comprehensive slope percentage calculator, your ultimate guide for mastering the intricacies of expressing slopes in percentages. Whether you’re tackling a math assignment or deciphering the meaning behind road signs, you’ve landed on the perfect resource. In this detailed guide, we’ll delve into the following key areas:

Calculating Slope Percentage:


  • Measure the Rise: Determine the vertical distance the terrain rises or falls. Remember to make this value negative if you’re moving downhill.
  • Measure the Run: Identify the horizontal distance covered by the slope.
  • Compute the Slope: Divide the rise by the run.
  • Convert to Percentage: Multiply the result by 100 to express it as a percentage.


The formula for slope percentage is elegantly summarized as follows: Slope Percentage=RiseRun×100Slope Percentage=RunRise​×100

🙋‍♂️ If you crave a deeper understanding of the rise over run formula, check out our specialized calculator.

Converting Degrees to Slope Percentage:


  • Degrees to Slope Percentage: Slope Percentage=tan(d)×100
  • Slope Percentage to Degrees: Angle=arctan⁡(Slope Percentage100)Angle=arctan(100Slope Percentage​)

Ensure that the input angle falls within the range of -90° to 90° (excluding these values).

Dive into the intricacies of angles with our dedicated arcus tangent calculator.

Using the Slope Percentage Calculator:

Our tool is designed for simplicity. Input either the rise and run or the angle in degrees, and witness the instantaneous calculation of the slope percentage. The tool operates in reverse as well – input the slope percentage, and watch the angle in degrees materialize. If you provide either the rise or the run, the missing value promptly appears.

⚠️ Note: Exercise caution to input angles between -90° and 90°, excluding these specific values.

Frequently Asked Questions (FAQ):

  1. Can slope percentage be negative?
    • Indeed, it can. A positive slope denotes upward terrain, while a negative slope signifies a descent. The magnitude of the slope percentage indicates the steepness of the ascent or descent.
  2. Can slope percentage exceed 100%?
    • Absolutely! A 100% slope corresponds to a 45° angle. Slopes surpassing 100% are notably steeper, escalating towards infinity as the angle approaches 90°.
  3. How long is a ramp with a 1m rise and a 5% slope?
    • The run of the ramp is precisely 20m, a result derived from the slope percentage formula: Slope Percentage=RiseRun×100Slope Percentage=RunRise​×100.
  4. Is a road with a 5% slope considered steep?
    • Not particularly. A 5% slope implies a modest rise of 5 meters over a 100-meter run, translating to an angle of less than 3 degrees. The perception of steepness varies subjectively.