How to Reduce PDF Size to 100 KB, 200 KB or 1 MB

You've filled in the application, attached your documents, and the portal says the file is too large. Many job, admission, scholarship and visa portals cap each upload somewhere between 100 KB and 2 MB, while a single page photographed on a phone can easily be 1.5 MB on its own. This guide shows how to get a PDF under the limit without making it unreadable, using free tools that run in your browser, so your documents are never uploaded anywhere.

The quick answer

1. Open the free PDF Compressor and drop in your PDF.
2. Choose Target size and enter the portal's limit, for example 200 KB.
3. Click Compress to under 200 KB. The tool tries smaller and smaller settings and stops at the first one that fits.
4. Open the downloaded file and check that names, numbers and stamps are still readable before you submit it.

If the file can't get under the limit while staying readable, the tool tells you the smallest size it managed. Then you need fewer pages: see method 4.

Why your PDF is so big

Text costs almost nothing in a PDF. Pictures cost a lot, and a scanned or photographed page is one big picture. We measured test files built to match typical phone scans and reports:

What's in the PDF	File size
6 pages of typed text	2 KB
One A4 page photographed with a phone	about 1.6 MB
A 3-page scanned document	4.9 MB
A 4-page report with one photo per page	5.6 MB

So making a PDF smaller almost always means making the pictures inside it smaller: fewer pixels and stronger JPEG compression. Everything else is a rounding error.

First, work out what kind of PDF you have

Open the PDF and try to select a sentence with your mouse or finger. The answer decides which method works best:

• You can select the text and there are photos (reports, brochures, CVs with a picture): use method 1. The text stays sharp and searchable.
• You can't select anything, because the pages are pictures (made by a scanner or a phone scanning app): use method 2.
• You only have photos of the pages, not a PDF yet: use method 3.
• You can select the text and there are no pictures, but it's still too big: it is probably very long. Use method 4.

Method 1: shrink the photos, keep the text

In the PDF Compressor, start with Balanced, which brings photos down to about 150 DPI for their size on the page. If that isn't enough, try Strong (about 100 DPI), or Target size with your limit. Only the JPEG photos are re-encoded, and each one is replaced only when the new version is clearly smaller. Text, fonts, tables and links are not touched.

In our test, a 4-page report with a large photo on every page went from 5.6 MB to 347 KB on Balanced and to 76 KB on Strong, and its text could still be selected and searched.

Method 2: scanned documents

Scans are where most of the size comes from, and they shrink well. Here is what each setting did to a 3-page A4 document photographed with a phone (4.9 MB):

Setting	Result	How it looks
Balanced	905 KB	Sharp, prints well
Strong	410 KB	Clear on screen
Scanned document	533 KB	Clear on screen
Target size: 200 KB	187 KB	Softer, but every word readable
Target size: 100 KB	Not possible	Smallest readable version was 172 KB

Scanned document redraws every page as a fresh image. It helps most with scans that are stored inefficiently, such as files from office scanners that keep several layers per page. With phone scans like ours, which are already one JPEG per page, Strong did slightly better, so it's worth trying both. Target size tries both kinds of setting for you.

The 100 KB row is the important lesson: a readable scanned page needs roughly 60 KB at the very least, so three pages can't fit in 100 KB. The tool says so instead of handing you an unreadable file.

Method 3: photos of pages (and very tight limits)

If you photographed the pages yourself, turn them into a PDF first, then compress it:

1. Open Image to PDF, add the photos and put them in order. Choose A4 and Smaller file. Photos are turned upright automatically, so portrait shots don't end up sideways.
2. Click Convert to PDF and download it. Our one-page photo became a 375 KB PDF.
3. Put that PDF through the PDF Compressor with Target size. At 100 KB, our page came out at 65 KB and was still readable.

Better photos make smaller files. Lay the page flat in good, even light, fill the frame with the page, and avoid a patterned background. If your phone's scanner app has a "document" or black-and-white mode, use it for typed pages: clean white backgrounds compress far better than shadows and paper texture.

Need a photo or signature image under a size limit as well? The Image Compressor has the same idea for JPGs: choose To a target size and enter the limit.

Method 4: send fewer pages

When the limit is tight and the document is long, compression alone can't do it; every page has a minimum readable size. Two ways out:

• Remove pages the form didn't ask for. Blank backs of pages, instruction sheets and duplicates add size for nothing. Delete Pages shows a preview of every page; click the ones to drop. The removed pages are taken out of the file completely, not just hidden.
• Split the PDF if the portal has several upload slots (for example one per certificate). The PDF Splitter cuts it into parts of any size or into custom ranges such as 1-2, 3-4.

How many pages fit under each limit?

From our test scans of typed A4 pages, one page took about 300 KB at print quality (about 150 DPI), about 140 KB at screen quality (about 100 DPI) and about 60 KB at the smallest readable size. That gives a rough guide:

Upload limit	Sharp (≈150 DPI)	Clear on screen (≈100 DPI)	Smallest readable
100 KB	–	–	1 page
200 KB	–	1 page	3 pages
500 KB	1 page	3 pages	8 pages
1 MB	3 pages	7 pages	about 15 pages

Treat these as estimates. Pages full of small print, photos or colour backgrounds need more space; plain typed pages need less.

Keep it readable

A file that fits but can't be read is still a rejected application. Before you submit:

• Zoom to 100% and read the parts that matter: ID and roll numbers, dates, grades, stamps and signatures.
• Don't go below about 70 DPI. Under that, small print turns to blur. The Target size option stops there on purpose.
• Start from the original every time. Compressing an already-compressed file again loses detail twice over. If the result is too soft, go back to the original and try a larger limit or fewer pages.

Mistakes that get uploads rejected

• Renaming a photo to .pdf. Changing photo.jpg to photo.pdf doesn't make it a PDF, and portals check. Convert it with Image to PDF.
• Password-protected PDFs. Many portals can't open them. Open the file with its password and use your viewer's Print → Save as PDF to make an unprotected copy.
• Uploading a ZIP where a PDF is asked for.
• Screenshots of a PDF. They lose sharpness and are often bigger than compressing the original properly.
• Complicated file names. Some portals reject names with spaces or symbols. A simple name like matric-certificate.pdf avoids the problem.

Your documents stay on your device

The files people shrink for applications are exactly the ones you shouldn't hand to a random website: ID cards, passports, transcripts, bank statements. Every tool mentioned here runs inside your browser. The PDF is processed on your phone or computer and never uploaded to a server.