Compress a PDF without uploading it

How to Compress PDF

1. Add your PDF. Drag the file onto the drop zone. The current file size is shown so you know what you are starting from.
2. Pick a compression level. Choose Light, Balanced or Strong, or switch to target mode and type an exact size like 200KB. Balanced is the right answer for most documents.
3. Compress and preview. The tool reports the new size and the percentage saved, and shows a preview page so you can judge whether the quality still works for you.
4. Download. Save the compressed file, or step the quality up or down and run it again until you are happy.

Where PDF file size actually comes from

Before compressing, it helps to know what is making the file big, because it determines how much you can win.

In the overwhelming majority of oversized PDFs, the answer is images — usually scans. A page photographed at 600 DPI and stored with light compression can be several megabytes on its own. Twenty of those pages is a 60MB file, and no amount of clever restructuring will fix it. The images have to be resampled.

Text-only PDFs behave completely differently. A 300-page text document is often under 2MB already, because text is stored as instructions rather than pixels. If your file is mostly text and still large, the usual culprits are embedded fonts that were not subsetted, or an oversized logo repeated on every page. Those files have much less room to shrink — if you compress a text PDF and only save 5%, that is not the tool failing, it is the file already being efficient.

What each compression level does

The three presets trade quality against size in different places:

• Light — resamples images to around 200 DPI and strips metadata. Visually near-identical, typically 20-40% smaller. Safe for documents you will print.
• Balanced — resamples to roughly 150 DPI with moderate JPEG quality. Text stays crisp, photos soften slightly under close inspection. Usually 50-70% smaller. This is the right default for email and uploads.
• Strong — resamples to about 96 DPI with aggressive JPEG quality. Clearly lossy on photographs but perfectly readable on screen. Often 80%+ smaller. Use it when a hard upload limit leaves no choice.

An honest note on how this compressor works

Compressing a PDF properly means re-encoding the image data inside it, and browsers cannot do that with the ordinary PDF libraries. This tool renders each page and re-encodes it at your chosen resolution and quality, then rebuilds the document from those pages.

That approach is very effective on scans and image-heavy files, which is what people overwhelmingly need to compress. It has one real trade-off you should know about: on pages that contained selectable text, the text becomes part of the rendered page and is no longer selectable or searchable.

So: if your PDF is a scan, compress freely — the text was never selectable anyway. If your PDF is a text document and you need it to stay searchable, compress lightly or not at all, and consider whether the file is genuinely too big in the first place. If you need both small and searchable, run the compressed file through the OCR tool afterwards to add a text layer back.

Hitting a specific size limit

Plenty of portals enforce an exact cap — 100KB for a government form, 2MB for an email attachment, 5MB for a job application. Guessing at quality settings until you land under the limit is tedious.

Target mode does the searching for you: name a size and the tool repeatedly re-encodes at different quality levels, narrowing in until it finds the highest quality that still fits. There are dedicated pages for the most common targets if you want to jump straight there.

Frequently asked questions