PDF too large to upload? How to get under the size limit
Rejected by a submission portal because your PDF exceeds the size limit? Here is how to shrink a PDF safely while keeping it readable, plus fallbacks when compression alone is not enough.
Why PDFs get so heavy
Almost always, the weight comes from images inside the PDF — scanned pages, embedded photos, high-resolution figures. A text-only PDF stays in the hundreds of KB, while a scanned page alone can be several MB.
Upload caps vary by system: 2 MB, 5 MB, 10 MB are all common. Check the form's error message or notes first so you know how much you need to cut.
Fix 1: Run it through a PDF compressor
Compression re-encodes the images inside the PDF, often cutting the size in half or better for image-heavy files, with little visible difference.
Our PDF compressor runs entirely in your browser, so confidential documents like contracts or applications are never uploaded to a server. Always open the result once and confirm the text is readable before submitting.
Fix 2: Remove unneeded pages
If only some pages are required, deleting the rest is the quickest size win. Keeping 3 pages out of 10 cuts the file dramatically without touching quality.
The PDF page-removal and split tools let you extract just the range you need, right in the browser. Fewer pages beats lower quality when both options are open.
Fix 3: Split and submit in parts
If the portal accepts multiple files, splitting the PDF into part 1 and part 2 gets each file under the per-file cap.
Confirm first that split submissions are allowed — some portals explicitly require a single combined file.
Rescanning? Fix the scanner settings
If you control the scan, lowering resolution from 600 dpi to 300 dpi and switching from color to grayscale shrinks files enormously.
For text documents, 300 dpi grayscale is perfectly readable, and a clean rescan often beats aggressive compression.
When NOT to compress
Documents where fine print or stamps matter to a reviewer (ID documents and the like) can become unreadable if over-compressed and get bounced back. Zoom in and verify after compressing.
Digitally signed PDFs may lose their signature validity when modified. Submit signed files as-is, or request a lighter version from the issuer.
Summary: compress → trim pages → split
Work through it in order: ① compress the whole file, ② remove pages you don't need, ③ split as a last resort. That sequence balances quality against the requirement best.
Filewisp provides PDF compression, page removal, splitting, and merging — all free and processed in your browser, which suits confidential submission documents.