Compress PDF
Reduce the size of your PDFs to email them, attach them to forms or save space, while keeping them clear to read. This tool processes the file on a secure server and deletes it immediately after delivery.
Drag your files here
or click to select
How to compress PDF in 4 steps
Upload the file
Drag the PDF into the upload area or click to select it.
Choose the level
Select light compression to preserve quality or strong for the smallest possible size.
Compress
Click Compress PDF and wait a few seconds while the file is optimised.
Download the result
Download the reduced PDF. The uploaded file is deleted from the server right after the download.
Why a PDF gets large
In most cases, a PDF's weight comes from images. Scanned documents, high-resolution photos and screenshots take up far more space than text. Embedded fonts, thumbnails and metadata accumulated over several edits also grow the file without you noticing.
Compressing a PDF mainly means recompressing those images to a resolution suited to screens and ordinary printing, plus removing unnecessary data. The result is a lighter file that opens and loads faster, without changing the document's content.
Quality vs size: what to expect
Compression is a trade-off: the smaller the file, the more likely you are to notice a loss on very detailed images. For text documents and scanned contracts, strong compression usually shrinks the size a lot without hurting readability. For catalogues full of photos, the light level is the safer choice.
Be realistic about expectations: the reduction depends on the content. A PDF that is already just text has little to compress, while one full of images can shrink dramatically. If your goal is to get under a specific limit, such as a 25 MB email attachment, start with the strong level and adjust if you need more quality.
Privacy in this tool
This is one of the three on the site that use a server. The file travels encrypted, is compressed and deleted right after delivery — no copy is kept.
The limit is 50 MB
This is precisely the case where it hurts most, because whoever needs compression usually has a large file. Above 50 MB the upload is refused before it leaves your computer.
If your PDF exceeds that, it is normally a document scanned at high resolution. The route is to split it into smaller blocks, compress each one and merge them back — all three split and merge operations run in your browser, with no server limit.
What compression does, and what it does not
The reduction comes mainly from images: they are resampled to a resolution matching the level you choose. A text-only document is usually already close to the minimum, and in those cases the saving is small — not a failure of the tool, simply no excess to cut.
Choose the level with the destination in mind: maximum compression suits email and on-screen reading; high quality preserves images for printing. And keep the original: compression discards information permanently.
Use cases
- Shrink a PDF to fit an email attachment limit
- Get online forms and registrations to accept the upload
- Save space when archiving many documents
- Speed up the loading of PDFs published on websites
- Send scanned documents through messaging apps
Frequently asked questions
How much smaller will the file get?
It depends on the content. PDFs with many images can shrink a lot, while text-only files reduce little because they are already light.
Will the quality get worse?
At the light level the difference is minimal and rarely noticeable. At the strong level, very detailed images may lose sharpness, but text stays readable.
Is my file stored on the server?
No. The file is deleted immediately after delivery. We keep no copies and do not use the content for any other purpose.
Why does this tool use a server when others do not?
High-quality compression needs processing that does not run well in the browser alone. Tasks like merging and splitting PDFs, on the other hand, work 100% on your device.
Is there a size limit?
There is a per-file limit on free use to keep the service fast for everyone. The premium plan raises that limit.
General questions about the site
- Is it free?
- Yes — no sign-up, no usage limit and no watermark.
- Does it work on mobile?
- Yes, straight from your Android or iPhone browser.
- Do I need to install anything?
- No. No software, no extensions.
- Is my file sent to a server?
- On tools marked as local, no — the file never leaves your device. Only three tools use a server, and each says so on its own page.
How this works inside, and what the site does not do, is on the About page.