This guide provides step-by-step instructions on how to measure and adjust the incline of a treadmill. This is particularly useful when calibrating, and adjusting your treadmill for use with apps that use incline data like Zwift, or our Kinni app.
Incline terminology
There are 3 different ways in which treadmill incline can be defined:
1. Levels (which is usually a number)
2. Percentage (%)
3. Degrees (°)
Levels
Levels are the number of stops between the minimum incline and the maximum incline of a treadmill.
The level values do not necessarily translate to a percentage (%), or degrees (°) of incline, and you will need to contact the manufacturer for the details. Some manufacturers use levels to enable granular control over the incline without the need to implement a digital system on the display screen.
Percentage
The percentage incline is defined as, for every 100 metres forward, you climb a number of metres up.
So, for instance, a 2% incline would mean: for every 100 meters you run, you climb 2 meters vertically.
This is the easiest way to think about real-world incline.
Degrees
And, finally… the most complicated one! The degree of the incline is defined as the angle (in degrees) of a slope in relation to the direction of gravity. So, for instance, at 0° a treadmill’s running board would be level with the ground, and at 2.9° it will have a 5.0% incline.
The good news is that the use of degrees is uncommon, however, it is good to understand the difference. Importantly, that degrees and percentage are not the same thing, but one can be used to calculate the other.
Degrees vs Percentage
There is a direct relationship between degrees and percentage incline which is defined as follows:
To convert from degrees incline to percentage incline use:
percentage = tan(x°) × 100
To convert from percentage incline to degrees incline use:
degrees = tan-1(x%/100)
How to measure your treadmill’s incline
What will I need?
To get an accurate incline measurement you will need an inclinometer, also known as a “digital level”.
We have created an inclinometer that you can install on your smartphone. It ships with the Kinni app, and we’ve written a guide on it here.
How to measure the incline
- All measurements will be in relation to the floor as this provides a consistent measuring point.
- We will be assuming that the floor is level on which the treadmill is placed.
- The inclinometer needs to be placed on a flat area on the treadmill and parallel (inline) with the foot rails – see this guide for a photo reference.
Step 1 – Calibrate your incline
To get an accurate measurement it is important to calibrate your incline before starting. This feature is available on most good treadmills.
Step 2 – Measure the minimum incline
1. Turn your treadmill on.
2. Keep clear of the running belt and start the treadmill.
3. Put the treadmill on the lowest incline setting, typically “Level 0”.
4. Measure the incline and make note of the value.
Note: It is common for treadmills to have a minimum incline of between 0-2% (0-1.2°) incline.
Step 3 – Measure the maximum incline
1. Turn your treadmill on.
2. Keep clear of the running belt and start the treadmill.
3. Put the treadmill on the highest incline setting, typically “Level 20”.
Note: The maximum incline might not be available as a button on the screen so use the incline “+” until it does not change anymore.
4. Measure the incline and make note of the value.
Calculate the true incline
To make the calculations a bit easier we have created a spreadsheet for your reference that calculates your actual incline degrees and percentage based on the measurements in step 2 and 3.
(It’s all about the simple things!)
Incline calculator spreadsheet
Automatic adjustment
To dynamically adjust the incline we have added an incline adjustment feature to our Kinni app which will automatically adjust all the incline settings for you! Any related statistics like distance, speed, energy expense, and elevation gained are also tracked in the app. This provides you with a greater deal of flexibility and more accurate running statistics.
How to adjust your 0% incline
To more closely simulate the “energy cost” or “intensity” of outdoor running, treadmills tend to have a 1-2% offset in incline. This means that the minimum level can be between 1-2% when the treadmill is showing 0% (or on level 0).
If you prefer not to have this adjustment from the onset, but the treadmill cannot physically reduce its incline further, you can raise the rear of the treadmill to level it to a true 0%.