Measure the result you actually have
Write down the intended width and height, then measure both printed dimensions with a ruler. If your layout includes white space, measure the intended outer rectangle separately from the visible image.
| What you see | What to check first |
|---|---|
| Both dimensions smaller by a similar percentage | Page scaling and selected paper |
| Image edges missing | Photo crop, printable area and borderless settings |
| Whole image visible, with white space | Image proportions and placement choice |
| Unexpected page count or tiny arranged photos | A second pages-per-sheet layout in the print dialog |
For example, a 10 × 15 cm rectangle printed at 9 × 13.5 cm has both dimensions at 90% of the target. That is consistent with uniform scaling, so check the print settings before resizing the source.
Match the PDF, printer setting and loaded sheet
Check all three together. If the project uses Letter paper, select Letter in the printing software and load Letter paper. If you are using A4, keep A4 throughout.
The photo size is a separate setting. A 5 × 7 inch photo may sit on a larger page. Selecting 5 × 7 paper for a Letter PDF changes the printing situation; it does not simply remove the empty area around the photo.
Find out whether the page is being resized
In desktop Acrobat, Fit resizes the page for the available print area. Actual size keeps its scale, but content that does not fit can be clipped. For a layout you want to preserve, start with Actual size and matching paper.
On Mac, open the PDF in Preview, choose File > Print and enter 100% in the Scale setting. Avoid adding a second pages-per-sheet arrangement to a PDF that already contains several photos.
Your iPhone may not offer an equivalent scale control. Check your printer manufacturer's supported software and instructions, or transfer the PDF to a computer where you can inspect the percentage.
Distinguish cropping from a sizing error
If the full photo has different proportions from the requested rectangle, preserving it can leave white space. Filling the rectangle instead removes some image content. Check which result you intended in Printmira's preview.
Borderless printing deserves a separate check. For example, Canon documents enlargement and possible edge cropping for the G4080 series. Behavior varies by printer. Consult your model's instructions; where supported, try a normal bordered setting as a comparison.
A white border can also be related to the printer's printable area. Changing the crop inside the app will not necessarily change that hardware limit.
Change one setting and print one test
Keep the same PDF, change one setting, then measure again. Note the paper choice, scaling option and measured dimensions. This gives you a useful comparison without mixing several changes.
If you need to change the layout, Printmira lets you edit and preview the project for free. Generating a replacement photo PDF requires Pro. Check the page preview before creating it, and verify one physical print before using more photo paper.
Prepare your next print.
Set the dimensions and inspect the page in Printmira. Creating, editing and previewing are free. Generating a photo PDF requires Pro.
Get Printmira for iPhoneCommon questions
Will 100% scaling guarantee perfect dimensions?
It removes intentional percentage scaling in that print setting. Paper selection, printable-area limits and printer behavior still matter. Measure a test print.
Should I enlarge the photo to compensate?
Check the print setup first. A larger source can hide a scaling problem and produce the wrong size when you use another printer.
Why does the photo look smaller even when its box is correct?
Keeping an entire image inside a differently proportioned rectangle leaves space. Measure the visible image separately from the outer rectangle.
Sources & further reading
Official documentation for the printing options discussed in this guide.