Why Won't My Image Upload?
An image fails to upload for one of about six reasons. Read the error, then work down the list: size, dimensions, format, DPI, a damaged file, or a rule the site doesn't mention.
Triage table
| Likely cause | How to tell | Fix |
|---|---|---|
| File size over the limit | The error mentions KB or MB | Compress Image |
| Dimensions wrong | The error mentions pixels, width, height or “size” | Resize Image or KB + Dimensions |
| Format not accepted | The site lists JPG/PNG only, and yours is HEIC, WebP, AVIF | Convert to JPG |
| DPI missing or wrong | The rules say “300 DPI” or “resolution” | Change DPI |
| Damaged file | It opens partly, or half the picture is grey | Re-export or re-take the picture |
| A rule you can’t see | Everything seems to pass | Re-read the instructions; some portals check more than they list |
The quickest way: check everything at once
Instead of guessing, enter the site’s rules in the Image Requirement Checker and add your image. It lists format, dimensions, file size and DPI with a pass or fail, shows your value beside the required one, and marks rules it can’t check as “check yourself”, such as ink colour or whether a face is clearly visible. Then Fix these automatically hands the same file and rules to Fix Upload File, on your device.
The less obvious causes
- The extension lies. A PNG renamed to .jpg is still a PNG, and some portals look at the real format. WillItUpload reads the file’s own first bytes to identify it and never trusts the extension.
- A damaged file. A truncated or corrupted JPEG or PNG can look partly fine. WillItUpload checks the file’s own structure (the JPEG end marker, PNG checksums) and warns if something is wrong, rather than quietly producing a half-grey result.
- Orientation. Phone photos carry a rotation tag. Some systems ignore it, so the picture arrives sideways or with swapped dimensions. WillItUpload applies the tag so the output is upright.
- DPI that isn’t there. A file with no resolution value doesn’t pass a required DPI rule (the checker says “Not set in file”), and the fixer writes one.
- Too small, not too big. Some forms set a minimum size as well as a maximum.
Read the unit
KB and MB are a factor of ten from each other. And since portals disagree on whether a kilobyte is 1,000 or 1,024 bytes, WillItUpload reads a maximum cautiously (the smaller number of bytes) and a minimum the other way, so a file that passes our check passes either reading.
When the file really is fine
If every rule you can see passes and it still fails, the portal may be enforcing something it doesn’t list, or it may be a problem on their side. We can’t see those rules. After downloading a fixed file, the “did the application portal accept it?” question helps us learn when a requirement has changed.