5 Ways to Compress a PDF Without Losing Quality

PDFs are everywhere — reports, invoices, contracts, ebooks. But they can get large fast, especially with embedded images or scanned pages. Here's how to shrink them without destroying readability.

1. Use an Online Compressor

The fastest option. Upload your PDF, pick a compression level, download the result. No software to install.

The raatools PDF compressor does this in your browser — your file never leaves your device.

2. Reduce Image Resolution

Most PDF bloat comes from images. If your PDF has photos at 300 DPI but you only need it for screen viewing, downsampling to 150 DPI can cut file size by 50–70%.

3. Remove Embedded Fonts

PDFs often embed full font files. If the document uses standard fonts (Arial, Times New Roman, Helvetica), removing embedded fonts can save significant space. Most PDF editors have this option under "Save As" → "Reduce File Size."

4. Flatten Form Fields

Interactive PDF forms carry extra data for each field. If you're done editing, flattening the form bakes the values into the page and strips the form metadata.

5. Split and Remerge

Sometimes the most effective approach is to split the PDF into individual pages, compress each separately, and merge them back. This works well for mixed-content PDFs where some pages are text-heavy and others are image-heavy.

The raatools PDF merge tool makes the remerge step trivial.

How Much Compression is Too Much?

A good rule of thumb:

Use Case	Target DPI	Expected Savings
Screen/email	72–150 DPI	50–80%
Print (home)	150–200 DPI	30–50%
Print (professional)	300 DPI	10–20%

If text becomes blurry or images look pixelated, you've gone too far. Always preview the result before sending.