“File too large”, “Maximum size exceeded”, “The file must be smaller than 2 MB.” These errors appear at the worst moment, often on a form you have spent twenty minutes filling in. The fix is usually quick once you know what the form actually wants.
1. Find the real limit
Look for the number near the upload button, in the form’s instructions or in the error message itself. Note:
- The number and the unit. 500 KB and 5 MB differ by a factor of ten.
- Per file or in total. Some forms allow 2 MB per file but 10 MB for all attachments together.
- The file types it accepts. Sometimes the problem is not size at all: a form that wants JPG or PNG will reject any PDF.
Some systems count 1 KB as 1,024 bytes, others as 1,000. If you’re right at the edge, aim a little below.
2. See why the file is big
Check the file size in your file manager. Then think about what’s inside:
- Phone scans and photos are the usual reason. Each page is a large image.
- Long documents add up even when each page is modest.
- Text-only PDFs are often already small. If one is over the limit, it may contain embedded fonts or images.
3. Compress to the limit
With PDFTuck on Android:
- Tap Select PDF.
- Type the form’s limit: tap a preset (200 KB, 500 KB, 1 MB, 2 MB, 5 MB, 10 MB) or choose Custom.
- Tap Compress PDF. PDFTuck tries up to seven quality settings, measures each result, and keeps the best-looking one that fits.
- Look at the result. Ready to upload ✓ appears only when the file is at or under your limit.
- Preview the pages, then save the new file and upload that one.
You can also try the size check on our home page to see how big a cut you need before you start.
4. If it still doesn’t fit
PDFTuck says Best readable result when it can’t reach your limit while keeping pages readable. Then:
- Try stronger compression, and check readability in the preview.
- Remove pages the form doesn’t need.
- Split the document into parts if the form allows several uploads.
- Rescan at a lower resolution, in better light, or in black and white.
- Ask the organisation whether they accept a larger file or another way to submit it. A readable document matters more than squeezing it under a number.
Things that won’t survive compression
Depending on the document, compressed pages may become images. Searchable text, links and form fields may not be kept, and a digital signature is not valid in the compressed copy. If a form needs a digitally signed PDF, check with the organisation before you compress it.
Password-protected PDFs
If the PDF asks for a password when you open it, PDFTuck can’t compress it. Remove the password first with a tool you trust.