Odometer Offset and Factor - Explained


A Geotab device reports odometer readings. This is shown on the Vehicle Edit page.


However, in some cases the number reported on MyGeotab is not the same as what is seen on the vehicle’s dashboard. In that case, an odometer offset and/or factor can be added to get the number reported on MyGeotab to match with the one shown on the vehicle’s dashboard.

The odometer offset and odometer factor is shown by clicking on [+ More details].

An odometer offset allows you to adjust for absolute differences between the mileage displayed on your dashboard and the mileage provided by the on-board computer. When an engine is replaced its odometer should be reset to a lower value. Depending on your vehicle this may not be possible. If the mileage displayed on your dashboard is higher than the mileage provided by the on-board computer, simply enter the difference in the offset. If vice-versa, enter a negative value.

Under normal circumstances the odometer offset should be 0.

The odometer factor is used to adjust and scale differences between the mileage displayed on your dashboard and the mileage provided by the on-board computer.

For most vehicles, this value should be 1, meaning the on-board computer mileage is used. An odometer factor greater than 1 will scale the mileage by the odometer factor making readings larger, whereas an odometer factor between 0 and 1 will scale the mileage lower.



How to determine offset and odometer factor?

Below are the steps to take:

1) Record odometer readings off the vehicle’s dashboard along with the exact date and time of the recording. Take 3-4 readings (one day or trip apart). Ensure the vehicle is at a complete stop.

2) Go to engine measurements on MyGeotab to find the value recorded by the Geotab device.



3) Select your vehicle and the odometer diagnostic


 4) Find the date and time when the readings were made off the vehicle’s dashboard and record the value reported on MyGeotab at that same exact date and time.


Note: MyGeotab reports odometer readings in metric. Be careful when the vehicle’s dashboard is reporting in imperial.


5. Compare the two sets of values to determine the offset and/or factor. See example below.

Worked example:

1. Record the data as shown

Veh. dashboard (miles)

  Veh. dashboard (miles) Veh. dashboard trip distance (miles) MyGeotab (miles) MyGeotab trip distance (miles)
June 19th; 09:00am 114141.00 177.00 72219.91 106.18

June 18th; 12:00pm

113964.00 315.00 72113.73 188.98

June 17th; 7:00pm

113649.00 309.00 71924.75 185.59

June 16th; 8:00am

113340.00   71739.16  


2. Since the trip distance from the dashboard and MyGeotab do not correlate, this is an indication that there is an odometer factor. The factor is calculated as follows:



Veh. dashboard trip distance (miles) MyGeotab trip distance (miles) factor
177.00 106.18 0.6
315.00 188.98 0.6
309.00 185.59 0.6

If the odometer factor is 1, the odometer reading only has an offset. Skip Step 3.


3. The odometer reading from MyGeotab is then recalculated with the factor and the offset is calculated from there.


MyGeotab (original) MyGeotab (with factor)
72219.91 120366.52
72113.73 120189.55
71924.75 119874.58
71739.16 119565.26


4. The offset is calculated from the dashboard reading and the recalculated MyGeotab reading.



MyGeotab (with factor) Veh. dashboard (miles) offset
120366.52 114141.00 6225.52
120189.55 113964.00 6225.56
119874.58 113649.00 6225.58
119565.26 113340.00 6225.26

So you have now confirmed that there is an offset of 6225 miles. This is what you will now enter in as your offset. 



Note: If there is only an offset, the odometer reading on the Vehicle Edit page can also be updated by typing in the reading from the vehicle dashboard. On the next vehicle ignition, MyGeotab will automatically add in the offset.



Vik Sridhar

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