How to reduce a PDF to 100 KB (or 200 KB) for upload forms

Some upload forms don’t accept “a smaller PDF”. They want a number: under 100 KB, under 200 KB, sometimes under 50 KB. A scan of a single page is often 1–3 MB, so you may need to shrink it ten or twenty times. Text can stay sharp while you do that. Photos will get softer, and that’s the trade.

Shrink it, then check the size

1. Open Compress PDF and select the file. Files up to 100 MB are fine.
2. Choose Strong when the limit is 100 KB or the PDF is mostly scans. Choose Recommended first if the file has photos you want to keep closer to the original.
3. Download the result and look at the file size. If it is already under the limit, you’re done.

Compress PDF doesn’t type in a target like “100 KB” — image compression does, PDF compression uses a quality level. For a document that’s really one photo or a scan of a form, the image tool is often the better route: export the page or start from the photo, then use Compress image with Target size set to 100 or 200 KB and save as JPG.

If it’s still over the limit

• Turn images gray. Grayscale PDF leaves the text as text and drops the colour from photos and scans, which is often a big saving on forms.
• Delete pages the form doesn’t ask for. Cover sheets and blank backs count. Use Remove pages.
• Upload it in parts. If the portal allows more than one file, Split PDF can cut the document into pieces that each fit.

Read the form’s limit before you start. 200 KB is much easier than 100 KB, and some portals also want JPG instead of PDF. A passport-style photo is an image job, not a PDF job — use Compress image and crop it first.