How to Compress a PDF for University and Job Portal Upload Limits (Free)

By Pritom Dash · Published October 21, 2026

You finish the assignment, export the PDF, go to upload it — and the portal says the file is too big. Or an application form wants your certificates “in PDF, max 200 KB”. Here is how to make a PDF small enough without making it unreadable, and how to keep the text selectable when that matters.

Why PDFs get big

Text is tiny. A 20-page essay with no pictures is usually well under 1 MB. What makes PDFs big is images: photos, scanned pages, screenshots and high-resolution charts. A single phone photo can be 3–5 MB, and a scanned document is one large image per page. So compressing a PDF is almost always about the images in it.

The two ways to compress

Shrink the images and keep everything else. Each oversized image is resized to the resolution it actually needs at the size it is shown — about 150 DPI is sharp on screen and in print — and saved as an efficient JPEG. Text, links and vector graphics are untouched, so the text stays selectable and searchable. This is what ParaFree calls Light.

Turn every page into one image. Each page is rendered as a picture at a lower resolution and saved as a JPEG. This makes the smallest file, but the text is no longer real text: you cannot select it, search it or have it read by a screen reader. ParaFree calls this Strong.

When selectable text matters

For a CV, keep the text selectable. Applicant tracking systems read the text in your PDF; a CV that is just an image of text may be read as empty. The same goes for anything that will be searched, run through a similarity checker or read aloud. For a scanned certificate or a page of photos, it does not matter — the page was already an image.

Compressing to an exact target size

Upload pages usually tell you the limit: 1 MB, 2 MB, 5 MB, or for forms 100 KB, 200 KB or 500 KB. ParaFree’s Compress PDF has a Target size option for exactly this. Pick 100 KB, 200 KB, 500 KB, 1 MB or 2 MB, or type your own limit, and it:

1. keeps your original if it is already under the limit;
2. tries Light first, so your text stays selectable if that is enough;
3. otherwise turns the pages into images and searches for the highest resolution and quality that still fits;
4. stops at about 72 DPI rather than make the pages unreadable — and if even that is too big, gives you the smallest file it made and says so.

The result always tells you the size before and after, and whether the text is still selectable. It runs in your browser: no upload, no waiting — your file is processed on your device.

KB and MB are counted in two ways

Most websites and phones count 1 MB as 1,000,000 bytes. Windows File Explorer counts 1 MB as 1,048,576 bytes, so it shows a slightly smaller number for the same file. ParaFree uses the first way, like most upload pages. If a limit is very tight, aim a little below it.

When it will not fit

A 40-page scan will not fit under 200 KB at a readable quality — there is simply too much on the pages. If the tool tells you the target cannot be reached, try:

• Removing pages you don’t need, such as blank backs of scanned pages.
• Splitting the upload if the form allows several files.
• Scanning again in black and white or greyscale at a lower resolution — colour scans of text are much bigger than they need to be.
• Exporting from the original: if you have the Word file, export a fresh PDF with Word to PDF instead of compressing a scan of it.

Check before you upload

Open the compressed PDF and zoom in on the smallest text — a signature, a seal, a table. If you can read it comfortably, so can the person checking it. If not, choose a larger target and try again.

Need to put several files together first? Use Merge PDF, then compress the merged file. Photos of documents? Make them into one PDF with JPG to PDF before compressing.

ParaFree is a free AI writing suite with a document paraphraser that keeps formatting, a CV builder with ATS-readable PDFs, and in-browser PDF tools (PDF to Word, Word to PDF, JPG to PDF, compress and merge).

— Pritom Dash