5 Mistakes That Make Your PDF Look Broken on Mobile
You sent a PDF that looked perfect on your computer, but when a client or your boss opened it on their phone — the text was cut off, images wouldn't load, or everything looked misaligned. Here are the five most common causes, and how to avoid each one.
1. Non-standard page size
Documents created for print (like A3 or poster formats) often don't load correctly in mobile PDF apps that expect a standard aspect ratio. Fix: before sending, make sure the document uses standard A4 or Letter size unless there's a specific reason not to.
2. Fonts that aren't embedded
If the font used in the document isn't "embedded" inside the PDF file itself, other devices (including phones) substitute a default font — which shifts the entire layout and makes it look broken. Most creation tools (Word, Google Docs) embed fonts automatically on export to PDF, but it's worth double-checking in the export settings.
3. Files that are too heavy
A PDF with overly high-resolution images (for example, scans at 600 DPI when 150 would be enough) can take a long time to load on mobile, and on a weak connection may get stuck loading or appear only partially. Compressing the file almost always fixes this without meaningfully hurting readability.
4. Broken OCR text layers
If a document went through poor-quality OCR (automatic text recognition), it can create a "text layer" underneath the image that's misaligned — so when you try to copy text or search within the document on mobile, you get strange results or the view "jumps." The fix is to reprocess the document with a high-quality OCR engine rather than living with it.
5. Incorrect RTL directionality in bilingual documents
A document created in software that doesn't properly support RTL languages like Hebrew or Arabic can look fine on desktop (thanks to OS-level auto-correction) but fall apart on mobile, especially in simpler PDF apps. For a full breakdown of this issue and how to fix it, see our guide on RTL text in PDF conversion.
How to prevent all of this in advance
The most reliable rule: after creating or converting any important PDF, open it once on your phone (not just your computer) before sending it. It takes ten seconds and saves a lot of embarrassment.