Convert Pixels per millimetre to Pixels per metre
Convert Pixels per millimetre (px/mm) to Pixels per metre (px/m) instantly and accurately.
Conversion Formula
px/m = px/mm × 1000
About Pixels per millimetre
The pixel per millimetre (px/mm) is the resolution unit of precision in machine vision, flatbed scanning, and microscopy, where working distances are in millimetres. Industrial camera datasheets (Basler acA5472-17um, FLIR BFS-U3-200S6M-C) specify resolution in px/mm at defined field widths; a 20 MP sensor over a 100 mm field resolves 54.96 px/mm. ISO 12654 (archival scanning) specifies minimum 8 px/mm (≈ 200 PPI) for standard digitisation and 24 px/mm (≈ 600 PPI) for fine-detail originals. Digital pathology: Leica Aperio GT450 at 40× magnification achieves ≈ 4,405 px/mm. CMOS sensor pixel pitch has shrunk from 7.4 µm/px (≈ 135 px/mm, mid-2000s) to 0.64 µm/px (≈ 15,625 px/mm) for smartphone sensors in 2024. Since 1 in = 25.4 mm exactly, 1 px/mm = 25.4 PPI exactly. A 300 PPI photo print = 300/25.4 ≈ 11.81 px/mm.
About Pixels per metre
The pixel per metre (px/m) is the SI-coherent form of image resolution. Because 1 inch = 0.0254 m exactly (international inch, 1959), 1 PPI = 1/0.0254 ≈ 39.37 px/m and 1 px/m = 0.0254 PPI. EXIF (IEC 61966-3) stores resolution as pixels per inch (ResolutionUnit = 2) or pixels per centimetre (ResolutionUnit = 3); px/m is used when normalising to SI for scientific or GIS workflows. Satellite remote-sensing GSD is often given in metres per pixel (the inverse); WorldView-3 at 0.31 m/px panchromatic ≈ 3.23 px/m. An A4 document scanned at 300 PPI ≈ 11,811 px/m. 1 px/m = 0.0254 PPI ≈ 0.00254 px/cm.
Quick Reference Table
| Pixels per millimetre (px/mm) | Pixels per metre (px/m) |
|---|---|
| 1 px/mm | 1000 px/m |
| 2 px/mm | 2000 px/m |
| 5 px/mm | 5000 px/m |
| 10 px/mm | 10000 px/m |
| 25 px/mm | 25000 px/m |
| 50 px/mm | 50000 px/m |
| 100 px/mm | 100000 px/m |