How to convert dots per inch to dots per millimeter
dot/mm = dpi × 0.03937007874Because one dot per millimeter equals 25.4 dots per inch, you can also divide: dot/mm = dpi ÷ 25.4.
A dot per inch is smaller than a dot per millimeter: it takes 25.4 dots per inch to make one dot per millimeter.
Worked examples
- 1 dot per inch1 dpi × 0.03937007874 = 0.03937007874 dot/mm
- 5 dots per inch5 dpi × 0.03937007874 = 0.1968503937 dot/mm
- 10 dots per inch10 dpi × 0.03937007874 = 0.3937007874 dot/mm
- 20 dots per inch20 dpi × 0.03937007874 = 0.7874015748 dot/mm
- 100 dots per inch100 dpi × 0.03937007874 = 3.937007874 dot/mm
Dots per inch to dots per millimeter conversion table
Values are calculated by the conversion engine and rounded to 8 significant figures.
| Dots per inch (dpi) | Dots per millimeter (dot/mm) |
|---|---|
| 0.1 dpi | 0.0039370079 dot/mm |
| 0.25 dpi | 0.0098425197 dot/mm |
| 0.5 dpi | 0.019685039 dot/mm |
| 1 dpi | 0.039370079 dot/mm |
| 2 dpi | 0.078740157 dot/mm |
| 3 dpi | 0.11811024 dot/mm |
| 4 dpi | 0.15748031 dot/mm |
| 5 dpi | 0.19685039 dot/mm |
| 6 dpi | 0.23622047 dot/mm |
| 7 dpi | 0.27559055 dot/mm |
| 8 dpi | 0.31496063 dot/mm |
| 9 dpi | 0.35433071 dot/mm |
| 10 dpi | 0.39370079 dot/mm |
| Dots per inch (dpi) | Dots per millimeter (dot/mm) |
|---|---|
| 12 dpi | 0.47244094 dot/mm |
| 15 dpi | 0.59055118 dot/mm |
| 20 dpi | 0.78740157 dot/mm |
| 25 dpi | 0.98425197 dot/mm |
| 30 dpi | 1.1811024 dot/mm |
| 40 dpi | 1.5748031 dot/mm |
| 50 dpi | 1.9685039 dot/mm |
| 75 dpi | 2.9527559 dot/mm |
| 100 dpi | 3.9370079 dot/mm |
| 250 dpi | 9.8425197 dot/mm |
| 500 dpi | 19.685039 dot/mm |
| 1,000 dpi | 39.370079 dot/mm |
About the units
Dot per inch (dpi)
Dots (or pixels) per inch; 300 dpi is the usual target for high-quality print. One dot per inch equals 39.37007874 dots per meter (dot/m).
Dot per millimeter (dot/mm)
The dot per millimeter (dot/mm) is a unit of digital image resolution in the metric system. One dot per millimeter equals 1,000 dots per meter (dot/m).
Frequently asked questions
How many dots per millimeter are in one dot per inch?
There are 0.03937007874 dots per millimeter in one dot per inch, and this value is exact by definition.
How do I convert dots per inch to dots per millimeter?
Multiply the number of dots per inch by 0.03937007874. For example, 10 dpi × 0.03937007874 = 0.3937007874 dot/mm.
How many dots per inch are in one dot per millimeter?
One dot per millimeter equals 25.4 dots per inch. That is the reverse factor, 1 ÷ 0.03937007874.
What is 10 dots per inch in dots per millimeter?
10 dpi = 0.3937007874 dot/mm.
Is this dpi to dot/mm converter accurate?
Yes. Both units are defined exactly in terms of SI units, so the conversion factor is exact; results are shown to 12 significant figures by default and you can change precision in the converter. Calculations run in your browser using the same tested engine that generated this page.