Many portals refuse uploads that are too large, too small, or in the wrong format. Most problems come from scanning at too high a resolution or uploading a raw phone photo.
Fix the source first
- Scan at 150 to 200 dpi. 600 dpi makes the file several times larger without making text easier to read.
- Use black and white for text-only pages such as letters and result slips.
- Crop edges so you are not storing empty margins.
- Remove blank pages before you combine files.
Compress a PDF to a set size
Open Compress PDF, choose Target size and type the limit. Common limits have their own pages: 100 KB, 200 KB, 500 KB and 1 MB.
Smart mode keeps text sharp and shrinks only the pictures. Maximum mode turns pages into compressed pictures, which makes the smallest files but means text can no longer be selected.
Resize photos and signatures
A phone photo is thousands of pixels wide. A form usually needs a few hundred. Use the Image Resizer and set the largest file size, for example 20 KB or 50 KB.
| File size | Starting picture width |
|---|---|
| 10 KB | 150 to 200 px |
| 20 KB | 200 to 300 px |
| 50 KB | 400 to 600 px |
| 100 KB | 600 to 800 px |
| 200 KB | 900 to 1200 px |
If a file still will not upload
- Check the accepted format. Some portals want JPG, others PDF only.
- Avoid spaces and symbols in the file name.
- Split a long PDF into parts if the portal allows several uploads.
- Try another browser, and keep your original file untouched.
Frequently asked questions
Why does my phone photo get rejected?
Phone photos are often several megabytes and thousands of pixels wide. Portals usually want a few hundred kilobytes or less, so resize the picture first.
Is it safe to use an online tool for my documents?
The tools on this site run inside your browser and do not upload your files. Check this for any tool you use with personal documents.
More guides
Free tools you may need
Compress PDF
Reduce the size of your PDF files while keeping them readable.
Image Resizer
Resize and compress photos to exact pixels, cm or a target size in KB. Passport and portal presets.
Scan to PDF
Scan paper with your camera or photos. Make a PDF, searchable PDF, Word file, text or JPG.
JPG to PDF
Combine multiple JPG or PNG images into a single PDF document.