Odometer and Speedometer calibration

I have a Scion XA 2006 and recently bought new tires. The old tires were 185/60/15 and the new ones 195/60/15, making them slightly larger. I bought these because it was all that was available in the brand I wanted that was close to the old tire size. I have been told by several sources that the odometer and speedometer cannot be recalibrated. This seems strange since I know of many people who change tire sizes. is this true? I’m not wanting to reset the odometer, only to make it be accurate. By the way, even with the old tires, the odometer was a little less than 4% off and now it is around 6% off.

I suspect they can be calibrated. Find a speedometer shop. You may need to check in a large city.