How much smaller will my PDF get?

It depends heavily on what's inside the file. PDFs with large, high-resolution embedded images typically shrink the most — sometimes 60-90% — since image data is usually the biggest contributor to file size. A PDF that's mostly text was probably already small and won't shrink as dramatically.

Will compression make my PDF blurry?

At light and medium settings, image quality loss is generally hard to notice on screen. Maximum compression trades more visible quality for a smaller file, which is useful when file size matters more than print-level image fidelity, like for email attachments.

Does compression affect the text, or only images?

Text stays fully selectable and sharp at any compression level — this tool only re-encodes embedded raster images and optimizes font subsetting and internal PDF structure. Text is vector data, not pixels, so it isn't degraded by compression the way images are.

Can I compress a scanned PDF made entirely of images?

Yes, and scanned PDFs are often where compression makes the biggest difference, since every page is effectively one large image.

Will compressing remove any pages or content?

No. Compression only changes how existing content is encoded — every page, image, and piece of text in the original remains in the output, just stored more efficiently.

What's a realistic target if I need to get under an email attachment limit?

Try medium or maximum compression first and check the resulting size shown on screen; if it's still too large, the file likely has very high-resolution source images and may need pages split across multiple emails instead.

Can I undo compression if I don't like the result?

Since your original file never leaves your device, it's untouched on your computer — just re-upload it and try a lighter compression setting if the first result isn't what you wanted.

Is my file uploaded to a server?

No. Every operation on this page runs locally in your browser using JavaScript and WebAssembly. Your file is never transmitted anywhere, which also means it works without an internet connection once the page has loaded.

Is this PDF compressor free, and is there a file size limit?

Yes, this free online PDF compressor has no cost, no watermark on the compressed output, and no artificial file size cap — the only practical limit is your own device's available memory, since compression runs entirely in your browser rather than on a metered server.

How does this compare to reducing PDF file size in Adobe Acrobat?

Acrobat's file-size reduction requires a paid subscription for its full feature set and runs the compression on your desktop. This tool applies the same core idea — re-encoding embedded images and optimizing internal structure — for free, directly in your browser, with a live before/after size comparison so you can see the tradeoff before downloading.

Can I compress multiple PDFs at once, or only one file at a time?

This tool processes one PDF at a time so you can review its specific compression tradeoff before downloading; for several files, run each through individually with whichever compression level suits that particular document's content.

Does making a PDF smaller change its page dimensions?

No, compressing a PDF only changes how embedded images and internal structure are encoded — page width, height, and orientation stay exactly as they were, so the document still prints and displays at the same physical size.

What compression level should I pick for a PDF I plan to print?

Light or medium compression is the safer choice for anything headed to print, since maximum compression optimizes for on-screen file size over image fidelity — reserve the most aggressive setting for documents that will only ever be viewed digitally, like an email attachment or an internal reference copy.

Why does my compressed PDF still look large despite compression?

If the file is mostly text with few embedded images, there is inherently little to compress, since text itself takes up very little space compared to image data; a text-heavy PDF's file size will not shrink dramatically regardless of compression setting.

Will compressing a PDF affect its text quality or searchability?

No, compression targets embedded images specifically; text remains sharp, selectable, and searchable exactly as it was before compression.

Can I compress an already-compressed PDF further?

Running compression again can shrink it somewhat more if a more aggressive setting is chosen, but each additional pass reduces image quality further, since it is re-compressing images that have already lost some quality from the first pass.

Compress PDF

Shrink PDF file size by compressing embedded images and optimizing fonts.

Processed entirely in your browser. Your file is never uploaded anywhere.

Why compress PDFs with Tools Root

PDFs balloon in size mainly because of embedded images saved at unnecessarily high resolution, or fonts and metadata that don't need to be duplicated throughout the file. This free PDF compressor targets exactly that — the visual content and structure stay intact, but the file takes up less space and uploads or emails faster.

What actually happens during PDF compression

This tool re-encodes embedded raster images at a quality level you choose, and optimizes internal PDF structure like font subsetting and object streams. It does not rasterize your text into images, which is a shortcut some PDF size reducers use that makes text blurry and unselectable — text here stays exactly as sharp and searchable as the original, no matter how aggressive a compression level you pick.

A free alternative to paid PDF compression software

Reducing PDF file size is often locked behind a subscription in desktop editing software, or capped at a handful of free compressions per day on other sites. This online PDF size reducer offers every compression level — light, medium, and maximum — for free, with no daily limit, letting you shrink a PDF for email, upload, or storage as many times as you need.

Common use cases

Getting a scanned document under an email attachment size limit, shrinking a design portfolio PDF for faster web download, reducing storage costs for a large archive of digitized paperwork, preparing a file for a web form that enforces a maximum upload size, or compressing a resume or application PDF that a job portal is rejecting for being too large.

Before and after compressing a PDF

If your PDF is actually several documents that should be one file, Merge PDF combines them first so you only need to compress once. If a scanned PDF still isn't sharp enough to read after compression, OCR PDF can add a searchable text layer independent of the image quality. And if the compressed file still needs a professional finishing touch, Watermark PDF and Number Pages both work cleanly on an already-compressed document.

Why some PDFs compress far more than others

A PDF's compressibility depends heavily on what it actually contains. A document full of large, high-resolution photos has substantial room to shrink, since image data typically dominates file size, while a mostly-text report with few or no embedded images has comparatively little left to compress, since text content itself takes up very little space.

Picking a compression level for how the PDF will actually be used

A PDF being emailed or uploaded somewhere with a strict size limit benefits from a more aggressive compression setting, prioritizing a smaller file even at some cost to image sharpness. A PDF meant to be printed or viewed closely on a large screen is worth compressing more lightly, keeping embedded images crisp for those closer viewing conditions.

How to compress a PDF

1Upload the PDF you want to shrink.
2Choose a compression level, from light (best quality) to maximum (smallest file).
3The tool re-encodes embedded images and optimizes internal fonts and structure.
4Download the smaller PDF and compare the before/after file size shown on screen.

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