What are the factors that impact the accuracy of a caliper? The most important factor that impacts the accuracy of the measurement taken by a caliper is the skill of the operator. This is why it is important to choose the type of caliper that makes the most sense for the job at hand. If you choose a caliper that has more capabilities to complete an outside measurement, like a Vernier caliper, but do not know how to use it properly, you may negatively impact your accuracy. It is better to choose a caliper you know how to use in order to get a more precise and accurate measurement. Another factor to keep in mind is calibration. You want to make sure that if possible, your caliper is regularly calibrated. If you are working with an uncalibrated caliper (such as a one-purpose caliper like the inside caliper), then you will want to make sure that the measurement reference you are comparing it to is calibrated. Finally, to ensure accuracy of your caliper, you want to make sure that it always has a proper zero point. Mishandling of certain calipers can mess up the zero point as well as the eventual measurements.