Find the distance between your starting and ending elevation. In other words, mark your beginning and end point of the slope (or grade) you're looking to find. This is called your run.

Find your starting and ending elevation. You can use either an accurate elevation measuring device if you're working on a large building, or a ruler if you're simply in your backyard working on a small piece of land.

Subtract your ending elevation from your starting elevation. This will be your rise. If your ending elevation is higher than your starting elevation, then the number should be positive. If your ending elevation is lower, then the number should be negative.

Divide your rise (Step 3) from your run (Step 1) in order to find the slope. For instance, if you are measuring a distance of 12 inches and the elevation difference is 4 inches, then your slope is 6 divided by 12, which equals 0.5. Once again, if you are going uphill, your slope will be positive. But if you are going downhill, your slope will be negative.

Multiply your slope by 100 to find your grade. Grade is the same as slope but uses a percentage to indicate the measurement. In our example, a 0.5 slope means that it has a grade of 50 percent.