THE ESSENTIALS
Check the file’s pixel dimensions at the intended print size. Changing the DPI value alone does not create additional detail.
Stay within both upload limits
The customizer accepts JPG, PNG and WebP images up to 20 MB and 40 megapixels. These limits are independent: megapixels equal width multiplied by height in pixels, divided by one million. Compressing a JPG does not necessarily reduce its pixel dimensions.
Understand pixels and resolution
Pixel dimensions describe the amount of detail available. Pixels per inch (PPI) relate those pixels to the printed size; software sometimes labels this setting DPI. Changing this value alone does not make a small image sharper.
Example pixel dimensions for each size
These rounded dimensions correspond to roughly 150 pixels per inch at the mouse pad’s size. They are preparation examples within the 40 megapixel limit, not a print quality guarantee. The file must also stay within 20 MB. Original detail and cropping still matter.
- 26 × 21 cm: approximately 1,535 × 1,240 pixels.
- 45 × 40 cm: approximately 2,657 × 2,362 pixels.
- 90 × 40 cm: approximately 5,315 × 2,362 pixels.
- 120 × 50 cm: approximately 7,087 × 2,953 pixels.
Preserve the original detail
Use the original file rather than a screenshot or a compressed messaging app copy. If it exceeds the limits, export a copy with the mouse pad’s proportions and check its sharpness. Artificially enlarging a small image does not add missing detail. Heavy cropping or zooming reduces the usable resolution.
Leave a safety margin
Keep important elements 2 to 3 cm away from the border to avoid slight trimming.
Your questions
Do I absolutely need 300 DPI?
No. This is not an upload requirement. A 90 × 40 cm export at 300 pixels per inch is roughly 50 megapixels, which exceeds the customizer’s limit. Check the actual pixel dimensions rather than the DPI value alone, and contact Pinea if you are unsure about your file.
Is a phone photo enough?
It depends on its sharpness, dimensions and crop. Keep the original and check the resolution estimate in the customizer. If your phone produces HEIC files, export a JPG, PNG or WebP copy before uploading.
Why is a small file rejected?
A heavily compressed image can be below 20 MB while exceeding 40 megapixels. Check its width and height in pixels, then reduce its dimensions if needed while keeping its proportions.