When you need a PDF under 100 KB
Some application portals cap each PDF at 100 KB: one certificate, one ID proof, one receipt per upload field. It is one of the smallest limits you will meet for a PDF, and it is meant for a single page, not a full document.
Limits vary by portal and by field, so use the number shown next to the upload button rather than one from another form.
What to expect at 100 KB
The tool redraws each page as a JPEG image. It starts at 150 dpi and high quality, lowers the JPEG quality step by step, and reduces the resolution only if that is not enough, down to 50 dpi. It stops at the first setting that fits, so you get the sharpest version under 100 KB.
- One scanned page usually fits at a resolution where ordinary print is readable.
- Three or more pages often need a low resolution, and small print gets soft. The tool warns you when pages drop below 72 dpi; zoom in and check before you upload.
- A PDF made from Word or a website is often already under 100 KB. The tool checks first and tells you to upload it as it is, since converting text to pictures would not help.
- If nothing fits, it says so and shows the smallest size it reached, instead of handing you an unreadable file.
How to get under 100 KB
- Upload only the pages asked for. Split PDF extracts one page without changing its quality. This is the biggest saving.
- Rescan in greyscale at 150 dpi if you can. A clean greyscale scan compresses much better than a colour phone photo.
- Starting from a photo? Compress it with Compress image to 100 KB, then make the PDF with JPG to PDF.
Your PDF stays on your device
Most online compressors upload your PDF to their servers. Here, every page is rendered and rebuilt inside this browser tab, using the open-source PDF.js and pdf-lib libraries.
The page’s security policy tells your browser to block uploads, so the document can’t leave your device even by accident. You can check: open your browser’s developer tools, watch the Network tab, and compress a file. How InTheTab works
You’ll also see a few small requests to Google Analytics. That’s our visit counter, and it never receives your files. Privacy policy
Questions
How do I compress a PDF to 100 KB?
Pick the PDF above with the 100 KB target selected and press Compress PDF. The tool tries the sharpest settings first and stops at the first one under 100 KB. Download the result and check it before you upload.
Why can’t my PDF get under 100 KB?
It has too many pages or too much detail for 100 KB at a readable resolution. Upload only the pages the form needs, or rescan in greyscale, then try again.
Will the text still be selectable?
No. Pages are saved as images to make them small, so text becomes part of the picture. That makes no difference for a scan. Keep your original for anything you need to copy text from.
Can I compress a PDF below 100 KB on my phone?
Yes. It works in the browser on Android and iPhone. Pick the PDF from your files, compress and download. Nothing is installed and the PDF is not uploaded.