mm to Points Converter
A printer asks for a 3 mm bleed, your design software counts in points, and the bridge between the two is a factor of about 2.83.
Quick answer: multiply the millimetres by 72 and divide by 25.4, which is about 2.8346. So 1 mm is 2.83 pt, 3 mm is 8.5 pt and 25.4 mm is exactly 72 pt.
The millimetres to points formula
An inch is exactly 25.4 mm and holds 72 points, so one millimetre is 72 ÷ 25.4, about 2.8346 points.
Multiply the millimetres by 2.8346 to get points.
For 3 mm, 3 × 2.8346 is 8.5 pt.
For an A4 page of 210 mm, 210 × 2.8346 is 595.3 pt.
Points and millimetres
The point is a typographic unit of 1/72 of an inch, which makes it 0.3528 mm. Twelve points make a pica, and six picas make an inch (Made Good Designs: Points to inches converter).
Some older systems use a slightly different point, such as the 72.27 per inch version, so software may differ by a fraction of a percent.
Print files, PDFs and design tools all use points, while paper sizes and printers often quote millimetres.
How to convert mm to points step by step
- Write the size in millimetres.
- Multiply by 72.
- Divide by 25.4.
- Round to one or two decimals.
Example 1: a 3 mm bleed
- Start with 3 mm.
- 3 × 72 ÷ 25.4 = 8.50.
- The bleed is 8.5 pt.
3 mm = 8.5 pt
Example 2: an A4 page
- A4 is 210 by 297 mm.
- 210 × 2.8346 = 595.3 and 297 × 2.8346 = 841.9.
- The page is 595 by 842 pt.
A4 = 595 × 842 pt
Example 3: a 5 mm margin
- Start with 5 mm.
- 5 × 2.8346 = 14.17.
- The margin is 14.2 pt.
5 mm = 14.2 pt
The points figure is exact only when you keep all decimals, because 72 ÷ 25.4 repeats.
mm to points conversion table
| Millimetres | Points | Picas |
|---|---|---|
| 1 mm | 2.83 pt | 0.24 pica |
| 2 mm | 5.67 pt | 0.47 pica |
| 3 mm | 8.5 pt | 0.71 pica |
| 5 mm | 14.17 pt | 1.18 pica |
| 10 mm | 28.35 pt | 2.36 pica |
| 12.7 mm | 36 pt | 3 pica |
| 20 mm | 56.69 pt | 4.72 pica |
| 25.4 mm | 72 pt | 6 pica |
| 50 mm | 141.73 pt | 11.81 pica |
| 100 mm | 283.46 pt | 23.62 pica |
| 210 mm | 595.28 pt | 49.61 pica |
| 297 mm | 841.89 pt | 70.16 pica |
The highlighted row is 25.4 mm, exactly 72 pt, or one inch. The last two rows show the A4 width and height.
A quick mental shortcut for mm to points
Multiply by 3, then take off about 6 percent. So 10 mm is about 30 minus 1.8, or 28.2 pt.
Or remember that 1 mm is a little under 3 pt.
Mm to points for print and PDF
Designers set margins, bleeds and rules in points but often receive specifications in millimetres. A standard European print bleed is 3 mm, which is about 8.5 pt.
Converting once at the start prevents mismatches when a file goes to press.
Points to millimetres
To go back, divide the points by 2.8346, or multiply by 0.3528. So 12 pt is 4.23 mm, and 72 pt is 25.4 mm.
Both directions use the same relationship of 72 points to 25.4 mm.
Millimetres, points and pixels
Points and millimetres are physical units, so they convert without any resolution. Pixels need a PPI, with 96 PPI as a common web benchmark (Omni Calculator: Pixels to inches converter).
At 96 PPI, 1 mm is about 3.78 px.
Checking your answer
Divide the points by 2.8346 to recover the millimetres. If 8.5 pt gives 3 mm, the conversion is right.
The point figure should always be a little under three times the millimetre figure.
More worked values
An A4 sheet is 210 mm wide, which is about 595.3 pt. It is 297 mm tall, which is about 841.9 pt.
A line of 0.25 mm is about 0.71 pt, a common thin rule.
Checking in reverse
Multiply the points by 25.4 and divide by 72. A value of 595.3 pt gives back about 210 mm.
Bleed and margins
A 3 mm bleed on each side adds 6 mm to the width and height of a sheet. For A4 that makes a page of 216 by 303 mm, or about 612.3 by 859 pt.
Quick conversion answers
| Conversion | Result |
|---|---|
| 1 mm to points | 2.83 pt |
| 3 mm to points | 8.5 pt |
| 5 mm to points | 14.17 pt |
| 10 mm to points | 28.35 pt |
| 25.4 mm to points | 72 pt |
| 100 mm to points | 283.5 pt |
Where this conversion is used
Designers and print operators set margins, bleeds and rules.
Developers and engineers convert page sizes for PDFs.
Students and editors move between metric and typographic units.
Common mistakes to avoid
- Using 3 as the factor. That is about 6 percent too high.
- Dividing instead of multiplying. Millimetres to points gives a bigger number.
- Mixing points with pixels. Pixels depend on PPI.
- Using 72.27 by accident. Check the point system of your software.
Related converters
Why points are used in design software
Typography grew up around the point, so type sizes, line spacing and rules are all measured in it. PDFs and vector formats store page geometry in points for the same reason.
That is why a millimetre dimension from a printer must be converted before you type it into a layout program.
Common paper sizes in points
A4 is about 595 by 842 points, and a US Letter page is 612 by 792 points. A 3 mm bleed on each edge, about 8.5 pt, extends the artwork beyond the trim line.
Frequently asked questions
How many points is 1 mm?
About 2.8346 points.
How do I convert mm to points?
Multiply the millimetres by 72 and divide by 25.4.
How many points is 3 mm?
About 8.5 points.
How many points is an A4 page?
About 595 by 842 points.
How many mm is 1 point?
About 0.3528 mm.
How many points are in an inch?
72 points.
Sources
- Made Good Designs: Points to inches converter (madegooddesigns.com)
- Omni Calculator: Pixels to inches converter (omnicalculator.com)
