I need to get a PDF down to under 100 KB for an online application form, and everything I’ve tried either barely shrinks it or makes the text unreadable. The file is a 6-page scan, so does anyone know a tool that actually hits that limit?
For a 6-page scan, 100 KB is extremely tight, so no compressor can guarantee that without trashing readability. I would rescan in black and white at 100 to 150 dpi, crop every margin, and remove any blank pages. I learned the hard way that compressing an already oversized color scan rarely works well. If that still misses the limit, ask whether they accept separate files or a higher limit.
Honestly, 100 KB for six scanned pages is a tall order, and most compressors will butcher the text trying. Scans are just images, so the fix is at the source: rescan in black and white (not colour or greyscale) at 150 DPI, which often gets you near that limit while staying readable. If your scanner software has a text mode at 100 DPI, try that too.
Honest answer, 100 kb for 6 scanned pages is brutal, the trick is lowering the scan resolution, not finding magic software. If your on a Mac, Preview’s Reduce File Size filter actually works, just expect some fuzz. On Windows I’d rescan in grayscale at 150 dpi then print to PDF. What device are you working from?
A 6-page scanned PDF under 100 KB is usually unrealistic without making it unreadable. I would rescan at 100 dpi in grayscale, turn on OCR, and save as a searchable PDF, then try compressing it again. If the application accepts it, recreating the form as a text PDF instead of using scanned page images is the better route. I learned this the hard way with insurance uploads.
For a 6-page scan, 100 KB is very tight, especially if the form has small print. I’d try PDFcap and choose grayscale, 100 dpi, and strong compression first, then check that every page is still readable. If it still won’t fit, the application may need a photo-free, black-and-white scan rather than color.
I use Ghostscript at 100 to 120 dpi in grayscale, then OCR if needed. A six-page scan under 100 KB will lose some quality, so verify fields remain readable.
100kb for a 6 page scan is rough since its basically all images, no text to compress. What got it closest so far, and do you have the original scanner settings or just the PDF? I’d try rescanning at lower DPI (150 or even 100 black and white) before messing with compression after the fact, that usually helps way more than squeezing an already flattened file.
@SilentHunter that grayscale then print to PDF route is what I’d try too, it’s saved me on my old laptop more than once. I’m on Windows, so not sure if it’s the same on Mac, but Preview’s Reduce File Size always seemed gentle.
Six scanned pages under 100 KB is super tough. The simplest fix I learned the hard way with new hire forms is re-scanning in pure black and white, not color or grayscale, at 150 DPI. Color data eats up almost all the file size, so dropping it keeps the text readable while shrinking the file way down.
Getting a 6-page scan under 100 KB is really tough.
When I shrink massive client receipts, I usually run them through ILovePDF in grayscale mode to save space.
Did you try changing the color settings to black and white yet?
@phantom_midnight Checking if it’s still in color is the first thing I try on any scan because that is usually why they stay huge. Last week a client proof only hit the size after I converted it to black and white in Acrobat and the text stayed fine. I would try that before another online tool.
@LostThunder That pure black and white tip is the one that finally worked for me on school forms. I scan at 150 dpi straight to black and white, then check the small print before uploading. If it’s still over, I split the pages and send two files, since most portals accept that.