As we know One pixel/μm is equal to 1000 pixel/mm (1 pixel/μm = 1000 pixel/mm).

To convert Pixel/Micrometer to Pixel/Millimeter, multiply your pixel/μm figure by 1000.

Example : convert 25 pixel/μm to pixel/mm:

25 pixel/μm = 25 × 1000 pixel/mm = pixel/mm

To convert Pixel/Millimeter to Pixel/Micrometer, divide your pixel/mm figure by 1000.

Example : convert 25 pixel/mm to pixel/μm:

25 pixel/mm = 25 ÷ 1000 pixel/μm = pixel/μm