US Letter and A4 are different physical sizes. Match the document, print dialog and loaded stock deliberately, especially for forms and labels. A correct dimension conversion does not establish that your printer supports the sheet or can print to its edges.
On this page
| Size | Nominal dimensions in inches | Nominal dimensions in mm |
|---|---|---|
| US Letter | 8.5 × 11 | 215.9 × 279.4 |
| US Legal | 8.5 × 14 | 215.9 × 355.6 |
| US Tabloid | 11 × 17 | 279.4 × 431.8 |
| A4 | About 8.268 × 11.693 | 210 × 297 |
| A5 | About 5.827 × 8.268 | 148 × 210 |
| 4 × 6 photo | 4 × 6 | 101.6 × 152.4 |
| #10 envelope | 4.125 × 9.5 | 104.775 × 241.3 |
Letter and A4 do not swap without a layout decision
A4 is narrower and longer than Letter. A document designed for one can clip or change pagination on the other. Fit-to-page scaling may keep the page visible but change the physical size of a form or label. When dimensions matter, choose the correct document size and actual-size workflow rather than silently accepting the app’s default fit option.
Physical size and printable area
The sheet has an edge, and the printer may require nonprintable margins inside it. Borderless mode is a specific combination of model, paper and size; it can enlarge and crop the image. A “maximum paper size” field does not reveal every supported custom size, tray limit or borderless combination.
Keep scanning limits separate
A printer accepting Legal sheets does not automatically scan a Legal original on its glass. The feeder can have another scan-length limit again. Use the scanner and ADF specifications, not the print-paper table, to answer an original-size question.
Use exact conversions and sensible display precision
NIST defines one inch as exactly 25.4 mm. The converter uses that factor and shows rounded display values without changing its internal arithmetic. A-series sizes in our reference are nominal whole millimeters; their inch figures are converted approximations.
Before sending a dimension-sensitive job
- Read the physical stock’s product and size.
- Set the same intended page size in the document and print dialog.
- Choose permitted media and the correct feed path.
- Review scaling, orientation and printable margins.
- Make a plain-paper proof where the task requires accurate placement.
- Measure critical elements if the workflow depends on physical size.
Use the interactive size reference for a quick lookup. For label and envelope workflows, continue with their specific guides. Dimensions identify the sheet; official printer documentation identifies what works.
Sources and scope
Official references checked October 6, 2026. Model manuals apply to their named US edition; they do not establish support on another printer. The decision examples and workflow checklists are our editorial analysis. No physical printer test was performed for this guide.