Many government forms, job portals, and email services limit PDF uploads to 100KB or even 50KB. Here is how to get your file under that size for free, without installing any software.
Why do PDFs get so large?
PDFs grow in size mainly because of high-resolution images and scanned pages. A text-only PDF is usually small — often just a few kilobytes per page. But a single scanned page can be several megabytes because it is essentially a large photo saved inside the document.
That is why a 3-page scanned form can easily be 5–10MB, far above the 100KB limit many websites enforce.
Step 1: Open the Compress PDF tool
On PDFPremium.pro, open the Compress PDF tool. Everything runs inside your browser using JavaScript, which means your file is never uploaded to any server. This is faster and far more private than tools that send your documents to the cloud.
Step 2: Choose your target size
Set your target — for example 100KB or 50KB. The tool automatically lowers the image quality and resolution just enough to hit your target, while keeping the document readable. You do not need to guess quality percentages manually.
Step 3: Download and check the result
Download the compressed file and open it to confirm the text is still clear. If it looks too blurry, simply try a slightly higher target size, such as 150KB instead of 100KB.
Extra tips for the smallest possible size
- Remove unneeded pages before compressing — fewer pages means a smaller file.
- If your PDF is just text, export it as plain text first, then convert back to PDF. Text-only PDFs are extremely small.
- For scanned documents, grayscale usually saves a lot of space compared to full color.
- Combine these tricks for forms with very strict limits like 20KB.
Use our free Compress PDF tool — no signup, no upload, works in your browser.
Open Compress PDF →With these steps, almost any PDF can be brought under 100KB in a few seconds — completely free and completely private.