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What does the pixel measure?



David W. Flater


The pixel is often used as a unit of measurement in information technology. Unfortunately, there is not a simple, consistently-applicable answer to what it is a measure of. This report analyzes the pixel unit through the lens of metrology and shows how one entity, the pixel, actually gives rise to a group of different units.
NIST Interagency/Internal Report (NISTIR) - 8456
Report Number


Flater, D. (2023), What does the pixel measure?, NIST Interagency/Internal Report (NISTIR), National Institute of Standards and Technology, Gaithersburg, MD, [online],, (Accessed May 28, 2024)


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Created January 11, 2023