Why Page Sizes Matter
Choosing the right PDF page size affects printing, file sharing, and document presentation. Different countries and industries have preferred standards that you should know.
The Two Major Standards
ISO 216 (A Series)
Used internationally, especially in Europe, Asia, and most of the world:
- A4: 210 x 297 mm (8.27 x 11.69 inches)
- A3: 297 x 420 mm (11.69 x 16.54 inches)
- A5: 148 x 210 mm (5.83 x 8.27 inches)
The A series has a mathematical beauty: each size is exactly half the previous when folded.
North American Sizes
Used primarily in the US, Canada, and Mexico:
- Letter: 8.5 x 11 inches (216 x 279 mm)
- Legal: 8.5 x 14 inches (216 x 356 mm)
- Tabloid: 11 x 17 inches (279 x 432 mm)
Detailed Size Comparison
| Size | Inches | Millimeters | Points |
|---|---|---|---|
| A3 | 11.69 x 16.54 | 297 x 420 | 842 x 1191 |
| A4 | 8.27 x 11.69 | 210 x 297 | 595 x 842 |
| A5 | 5.83 x 8.27 | 148 x 210 | 420 x 595 |
| Letter | 8.5 x 11 | 216 x 279 | 612 x 792 |
| Legal | 8.5 x 14 | 216 x 356 | 612 x 1008 |
| Tabloid | 11 x 17 | 279 x 432 | 792 x 1224 |
A4 vs Letter: Key Differences
Dimensions
- A4 is narrower by 6mm (0.24 inches)
- A4 is taller by 18mm (0.71 inches)
- A4 has a longer, slimmer appearance
Practical Impacts
- Documents designed for A4 may get cropped when printed on Letter
- Letter documents may have extra margins on A4 paper
- Always check printer settings before printing
Which Size Should You Use?
Use A4 When
- Sharing with international audiences
- Creating documents for European/Asian markets
- Working with ISO-compliant organizations
- Publishing academic papers (common standard)
Use Letter When
- Printing in the United States
- Creating documents for North American businesses
- Working with US government agencies
- Local US printing shops
Use Legal When
- Legal contracts and agreements
- Government forms in the US
- Documents requiring more content per page
- Certificates and licenses
Converting Between Sizes
Use our Resize PDF tool to convert between page sizes:
- Upload your PDF
- Select target size (A4, Letter, etc.)
- Choose scaling mode
- Download resized document
Scaling Considerations
- Fit mode: Preserves all content, may add margins
- Fill mode: Fills page, may crop edges
- Stretch mode: Exact fit, may distort
Industry-Specific Standards
Academic Publishing
- A4 is the international standard
- Some US journals accept Letter
- Always check submission guidelines
Legal Documents
- US: Letter or Legal size
- International: A4
- Contracts often specify required size
Marketing Materials
- Brochures: Various A sizes common
- Flyers: A4, A5, or Letter
- Posters: A3 or larger
Technical Documentation
- Manuals: A4 or Letter
- Drawings: A3 or larger
- Schematics: Often A3
Custom Sizes
Sometimes standard sizes don't fit your needs:
Common Custom Uses
- Business cards: 3.5 x 2 inches
- Booklets: A5 or 5.5 x 8.5
- Square formats: 8 x 8 inches
- Banners: Various wide formats
Calculating Points
PDF uses points as the base unit:
- 72 points = 1 inch
- 28.35 points = 1 cm
- 2.835 points = 1 mm
Printing Tips
Before Printing
- Check your PDF page size
- Match printer paper settings
- Select "Actual Size" not "Fit to Page"
- Do a test print first
Avoiding Common Issues
- Cropped content: Wrong size selected
- Scaled content: "Fit to Page" enabled
- Blank margins: Size mismatch
- Cut off text: Margins too small
Related Tools
- Resize PDF - Change page dimensions
- Crop PDF - Trim margins
- Rotate PDF - Change orientation
Conclusion
Understanding page sizes ensures your documents print correctly worldwide. When in doubt, use A4 for international documents and Letter for North American audiences. Need to convert? Try our Resize PDF tool for instant page size changes.