Most home worksheets are designed for A4 paper, but smaller activity cards and larger posters need a little more thought. Choosing the right paper size before printing can save cropped edges, miniature text and several wasted sheets.
In the A series, a larger number means a smaller sheet. A5 is smaller than A4, while A3 is larger.
Paper size and scaling calculator
Compare portrait paper dimensions and estimate the largest proportional scale that fits the target sheet.
The calculation uses nominal sheet dimensions with both pages in portrait orientation. It ignores printer margins and does not crop or stretch the page. Real printable areas may need a smaller scale. Use Actual size / 100% for measurement-critical templates.
Free printable: Paper sizes & printing checklist
Download this one-page A4 sheet to print for home, classroom or childcare groups.
Common paper dimensions
| Size | Millimetres | Centimetres | A useful family use |
|---|---|---|---|
| A3 | 297 × 420 | 29.7 × 42 | Posters and shared drawing |
| A4 | 210 × 297 | 21 × 29.7 | Worksheets and instructions |
| A5 | 148 × 210 | 14.8 × 21 | Small booklets and activity sheets |
| A6 | 105 × 148 | 10.5 × 14.8 | Small cards and invitations |
Cutting an A4 sheet across its long dimension gives two approximately A5 sheets. Standard dimensions are rounded to whole millimetres, which explains small differences when you compare the numbers.
A4 and US Letter are different
US Letter measures 215.9 × 279.4 mm. It is wider and shorter than A4. A worksheet designed for one can lose content at the edges when printed on the other without scaling.
Check both the document size and the printer’s selected paper size. A printer may remember the setting from a previous job.
Actual size or fit to page?
Choose actual size / 100% when the printed dimensions matter, such as a ruler, fitting template or measured craft pattern. Print any calibration square supplied with the file and measure it before using the template.
For an ordinary quiz or reading sheet, fit to printable area can prevent cropping. It may reduce the content slightly to accommodate your printer’s unprintable margins.
Printing two pages on one sheet
The multiple-pages-per-sheet option can turn two A4 pages into smaller activities on one sheet. Check that the resulting writing spaces and type are still comfortable for the intended child.
Print one test sheet first, especially for double-sided cards. Check orientation and which edge the printer flips before sending a whole class set.
Further reading: Adobe A4 format guide; Paper-size reference.

