Compress PDF

🗜ī¸
Click to upload or drag and drop

PDF files only (Max 10MB)

ℹī¸ How it works:
  • Upload your PDF file
  • Pick a compression level with the slider
  • Download the smaller PDF

Reduce PDF File Size Online for Free

Shrink large PDFs so they're easy to email, upload, or store. Our compressor downsamples and re-compresses the images inside your PDF and subsets fonts, while keeping text and vector graphics perfectly sharp. Choose how much to compress with a single slider, and download the smaller file. No sign-up and no watermarks.

How to Make a PDF File Smaller

  1. Click the upload area above or drag and drop your PDF (up to 10 MB).
  2. On the next screen, set the compression level — lower for the smallest file, higher to keep more image detail.
  3. Compress and download your PDF.

Compression Levels

  • Maximum compression – images downsampled to ~72 DPI; smallest file, best for screen viewing and email
  • High / medium – images around 100–150 DPI; a good balance of size and clarity
  • Light compression – images around 200 DPI; keeps more detail for print-quality documents

Why Some PDFs Shrink a Lot and Others Barely Move

Compressing a PDF mostly means shrinking the pictures inside it. Text and vector graphics are already tiny, so there is very little to remove from them. This explains most of the difference people see.

  • A scanned document is really a stack of photographs of pages. It is almost all image data, so it usually loses most of its size — anywhere from half to nine tenths of it, depending on the resolution the scanner used.
  • A report or presentation with photos and charts usually comes down a good deal, depending on how many images it has.
  • A plain text document — a letter, an invoice, a contract exported from Word — may hardly change at all. There is simply nothing large inside it to compress.

So if your PDF barely shrank, it is usually because it was already small in the way that matters. That is not a failure; it means the file was efficient to begin with.

Key Features

  • Sharp text – text and vector graphics stay crisp; only embedded images are recompressed
  • Adjustable level – trade size against image quality with one slider
  • Image downsampling – large embedded photos are scaled down and re-compressed
  • Font subsetting – embeds only the glyphs the document actually uses
  • Never bigger – if compression wouldn't help, you get your original file back unchanged

When You Might Need This

  • An email that bounces back because the attachment is too large
  • An upload form or portal that refuses the file — job applications, tax filings and council forms are common culprits
  • A scanned document that came out enormous because the scanner used a high resolution
  • Sending a report or presentation through a messaging app with a tight limit
  • A document that takes too long to open or load on a web page
  • Archiving a lot of scanned paperwork without filling a drive
  • Attaching several PDFs at once, where the total is what matters
  • Sending something to someone on a slow connection or a limited data plan

Frequently Asked Questions

Upload it, move the compression slider, and download the result. For emailing, the higher compression settings are usually fine — the document is going to be read on a screen, and screen viewing does not need print resolution. Most email services accept attachments of 20 to 25 MB, but many workplaces set a lower limit of 10 MB, so that is the safer target to aim for.

Nearly always because of images. A scanner set to 600 DPI produces pages many times larger than the 150 DPI that reads perfectly well on a screen. Photographs pasted into a document keep their full camera resolution even when displayed small on the page. Other causes are embedded fonts and, occasionally, content left over from earlier edits that was never truly removed.

Use one of the lighter settings. The text in a PDF is never touched at any level — it stays perfectly sharp because it is stored as characters and shapes, not as pictures. What changes is the resolution of embedded images. At the lightest setting they are kept at around 200 DPI, which is good enough to print; at the heaviest they drop to about 72 DPI, which looks fine on a screen but soft on paper. If the document is only going to be read on screen, even the heaviest setting usually looks perfectly good.

Start in the middle. If the file still is not small enough, move towards maximum compression — for a document that will only ever be read on a screen, that is almost always acceptable. Choose a lighter setting when the PDF will be printed, or when it contains photographs or diagrams where fine detail matters.

If compressing wouldn't actually reduce the size (common with text-only or already-optimized PDFs), the tool simply returns your original file unchanged so you never end up with a larger document.

Yes. Compression is completely free with no sign-up and no watermark, and you can upload PDFs up to 10 MB. Files are processed for your download and not shared.

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