Compress a PDF to fit an upload limit

How this compression works, honestly

Every page is drawn as an image and saved again with JPG compression, at a resolution low enough to meet your target and high enough to read. If a target is set, the tool starts at 150 dots per inch and steps down until the PDF fits, and stops there. That method suits some PDFs very well and others not at all:

Kind of PDF	Result
Scans and photos of paper	Usually much smaller. These files are already images, often saved at high resolution.
Slides and brochures full of pictures	Usually smaller.
Text documents exported from Word or Google Docs	Often not smaller, because text is already compact. The tool then keeps the original and says so.

The trade-off: in the compressed copy, text cannot be selected, searched or read aloud by a screen reader, because each page is now a picture. Keep the original for anything that needs that, and use the smaller copy only where the size limit applies.

Common limits worth knowing

• Email: Gmail allows attachments up to 25 MB, and other providers are similar or lower. A PDF just under the limit can still bounce, so aim a little below it.
• School portals: each school sets its own maximum upload size, so check the assignment page and pick the next target down.
• Government and job forms: often 1 or 2 MB per document, and sometimes as little as 200 KB.

When compressing is the wrong fix

If the PDF is for a person rather than a form, sending it as a link avoids the limit altogether: the reader opens it in the browser at full quality, and you can see when it was opened. PDF to link takes files up to 95 MB.