Index Card 3×5 paper size
76.2 × 127 mm
3 × 5 inches · 7.62 × 12.7 cm · aspect ratio 1:1.67
Index Card 3×5 size is 76.2 × 127 mm. Those are the Index Card 3×5 dimensions a printer works to; the same sheet in centimetres, inches, points and pixels is below.
It is written 3x5 and 3 by 5 as often as 3×5 — the same sheet however it is typed. Sizes named by their inches like this one get asked for by the numbers rather than by a letter code, which is why the spelling varies and the sheet does not.
What Index Card 3×5 is for
The 3 × 5 inch index card is a North American standard and the reason "3 by 5" is shorthand for a small note. It is close to but not the same as ISO A6 (105 × 148 mm, or 4.13 × 5.83 inches), which is the international index card — A6 is wider and shorter, so a box or sleeve made for one does not fit the other.
Index Card 3×5 dimensions in every unit
| Unit | Width | Height |
|---|---|---|
| Millimetres | 76.2 mm | 127 mm |
| Centimetres | 7.62 cm | 12.7 cm |
| Inches | 3 in | 5 in |
| Points (PostScript) | 216 pt | 360 pt |
Index Card 3×5 in pixels
Pixel dimensions depend entirely on the resolution you are working at — there is no single "pixel size" for a sheet of paper. Index Card 3×5 size in pixels has every resolution, with file sizes and canvas setup.
| Resolution | Pixels | Use |
|---|---|---|
| 72 DPI | 216 × 360 | Screen preview only — far too coarse to print |
| 150 DPI | 450 × 750 | Draft printing, internal documents |
| 300 DPI | 900 × 1500 | The standard for commercial print |
| 600 DPI | 1800 × 3000 | Fine detail, line art, archival scanning |
Setting up a print document? Use 300 DPI and add 3 mm of bleed on every edge unless your printer specifies otherwise.
How Index Card 3×5 relates to the rest of the series
At 76.2 × 127 mm (3 × 5 inches) the aspect ratio is 1:1.667. This size is not part of a halving series, so there is no fixed scaling factor to the next size up or down — each one is defined on its own terms.
The closest ISO sheet by area is A7 at 74 × 105 mm — this size is 25% larger. The proportions differ, though: A7 is 1:1.414 like every A size, and this one is 1:1.667, so content laid out for one does not fill the other without cropping or white space.
About Index Card 3×5
3 × 5 inches, the standard US index card.
Other Cards sizes
| Size | Millimetres | Inches |
|---|---|---|
| Business Card (US) | 88.9 × 50.8 mm | 3.5 × 2 in |
| Business Card (EU) | 85 × 55 mm | 3.35 × 2.17 in |
Frequently asked questions
What size is Index Card 3×5 in mm?
76.2 × 127 mm.
What size is Index Card 3×5 in inches?
3 × 5 inches.
What size is Index Card 3×5 in pixels?
There is no single answer — it depends on resolution. At the print standard of 300 DPI it is 900 × 1500 pixels; at 72 DPI it is only 216 × 360.