1Drop your PDF documents into the box above, or pick them from your device — there is nothing to install and no account to create.
2Choose how hard to squeeze: the resolution and quality the embedded images are downsampled to. Text and vector artwork are never touched by it.
3Start the job and let the workers re-pack the file; your original is never modified in place.
4Compare the new size against the original, then download the compressed PDF file.
Compress PDF FAQ
How does Compress PDF actually make the file smaller?
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Concretely, embedded raster images are downsampled to a target DPI, fonts are subsetted to the glyphs actually used and the object streams are rebuilt — text and vector artwork are untouched and stay perfectly sharp. Nothing about it depends on you installing software: the job runs server-side and hands back a finished file.
How much smaller will my file get?
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That depends on what is inside the document rather than on how many pages it has. A file that is mostly text and vector artwork is already compact and will barely move. One built from scanned pages or high-resolution photographs is where the entire weight sits, and downsampling those images is what produces a large reduction.
Does the format of my file change how much I can save?
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Very much so. PDF fixes the page: fonts, vectors, raster images and text coordinates are frozen so every reader sees identical layout. That determines both the headroom available and whether the saving costs you anything in fidelity.
Is there anything specific to PDF I should know before compressing?
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Yes — a PDF is an object graph, not a page image, so text stays selectable and vectors stay sharp no matter what happens to the raster content inside it. It is worth knowing before you overwrite an original you might need again.
What is the most common mistake when compressing PDF documents?
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Compressing the same file repeatedly. Each pass on a lossy format is a fresh generation of loss and the savings shrink while the damage accumulates. Go from the original to your target in one step, and keep the original.
What do I get back, and can I control the trade-off?
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A single compressed document per input, at an image resolution and quality you choose rather than a fixed default. Text, vector artwork and the page structure are untouched either way, so what you trade away is detail in the pictures, never the readability of the file.
What can I upload to Compress PDF?
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Any standard PDF, including ones produced by a scanner, by a word processor or by a print driver. Files with an owner password that only restricts editing are handled; files that need a user password to open are not, and we do not attempt to break encryption.
Is there a file size limit on Compress PDF?
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Yes: free accounts process documents up to 25 MB each, which covers most reports and contracts but not a long scanned document at 600 DPI; Ghostscript and qpdf do the work. Scanned PDFs are the usual thing that exceeds it, and compressing the document first is normally enough to bring it back under.
Will Compress PDF lower the quality of my PDF documents?
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Text and vector artwork are objects rather than pixels, so they stay perfectly sharp at any zoom no matter what happens. Only the embedded raster images can degrade, and only if the operation you chose resamples them.
Can I run Compress PDF on several PDF documents at once?
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Yes — upload the set and they process in parallel under one set of settings, which is the point of doing a document workflow here rather than clicking through a desktop reader.
Do bookmarks, links and form fields survive?
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Outlines, internal links and annotations are preserved wherever the operation allows it. Digital signatures are the exception: any change to the file necessarily invalidates a signature, because that is precisely what a signature is for.
Does Compress PDF cost anything?
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No. Compress PDF is free without an account, and nothing is stamped onto the pages. Uploaded documents are deleted from the workers shortly after the job completes.