Speedometer Error Calculator

Following multiple requests, we came up with a Speedometer Error Calculator. This tool will allow users to calculate the speedometer error that results when replacing their wheels with different-sized ones.

By using this speedometer calibration calculator, you can now estimate how this change will impact the speed displayed on the dashboard and calibrate accordingly.

Original Tire Size

New Tire Size

Here’s How To Use This Speedometer Error Calculator

  1. Enter the details of the original tire size: width, profile, and wheel size.
  2. Enter the details of the new tire size: width, profile, and wheel size.
  3. Enter the speed at which the car is traveling. The result is the same, regardless if your speedometer is in miles or kilometers.
  4. Click the “Calculate” button.

Bonus: An additional table showing the speedometer error at different speeds (10-200) will be displayed.

Note: The calculator is in mph, but will be the same result for kmh.

What Is Speedometer Error (Speedo Error)?

Speedo error, also known as speedometer error or speedometer calibration error, is the difference between your speedometer reading and actual speed. Speedometer error appears primarily when changing wheels to different-sized wheels, but it can also be a result of excessive tire wear or suspension modifications.

You can correct the speedo sensors by recalibrating them. To do this, you need to take the car to a specialist that has access to the right equipment and tools.

How can this Speedometer Calibration Calculator help you?

The Speedo Error Calculator is useful for anyone looking to change the size of the wheels on their car. This tool will allow you to see how much your speedometer readings will differ from real speed, allowing you to calibrate your speedometer accordingly.

speedometer calibration calculator

If you are a car mechanic or tire technician, this calculator will also benefit you in calculating the impact of various-sized tires on car performance.

Let’s say you’re driving on the highway, and your vehicle’s dashboard indicates that you’re traveling at a speed of 70 mph. However, when another car passes you that is also going 70 mph according to their onboard GPS system, it seems like they are actually passing you much faster than they should be if your vehicle was truly going 70 mph.

In this case, there may be a speedo error, and the actual speedometer reading might be off by a few miles per hour. This could happen due to various reasons such as tire wear or size differences, which can affect the distance covered in one revolution leading to Inaccurate indication etc.

To fix this problem, one would normally have to recalibrate or reprogram their instrument cluster using specialized equipment so that the displayed speeds more accurately match real-world measurements.

Therefore, if you are swapping your wheels for bigger wheels yourself, you will need to visit a tire shop or local garage and have them recalibrate your speedometer. Correcting a speedometer is not a simple task and requires special equipment.