Save a smaller copy of a document without sending it anywhere. OpenPdfEdit can compress PDF files by reducing each image to the resolution it needs on the page. It is free, with no account, no watermark and no upload.
What makes most PDFs big is images, and what makes most images big is resolution nobody sees. A phone photo is 4,000 pixels across. Laid into a report at five inches wide it is stored at 800 dpi, for a screen that shows perhaps 150 and a printer that resolves 300.
So when you compress PDF files here, the app first works out how large each image is drawn on the page. Then it reduces the image to the level's resolution at that size. An image that appears at more than one size is judged by the largest, so a logo shown small in a footer and large on a cover keeps enough pixels for the cover.
Photographs are stored as JPEG. Charts, line art and screenshots are resized but kept lossless, because JPEG leaves a halo around every hard edge.
There are three levels to choose from when you compress PDF files.
Lossless. Rewrites the file without its edit history or unused data. Every image keeps every pixel.
Balanced. Also reduces images to 150 dpi at the size they appear on the page, and stores photos as JPEG. Sharp on screen and in ordinary office printing.
Smallest. Reduces images to 96 dpi and compresses photos harder. Fine on screen, softer when printed.
Before you choose, the dialog tells you how many images the document has and how sharply the sharpest one is stored, and it marks the level it suggests. A document with no images worth reducing starts on Lossless.
When you compress PDF files this way, the result is a new file. The document you have open is not changed, so you can compare the two and try another level if the first is not what you wanted.
Text, fonts, form fields and annotations are not touched. To compress PDF pages here is to work on their images and on nothing else.
Some images are left alone too. Formats the app cannot open are kept byte for byte: JBIG2, CCITT fax, JPEG 2000, 1-bit and 16-bit images, and images with an indexed palette. So is any image whose new version would not come out smaller.
That gives an honest answer to whether you can compress PDF without losing quality. With Balanced or Smallest, text and line drawings stay exact and images lose resolution, which is a loss. With Lossless nothing loses a pixel, and the saving is smaller.
How far you can compress PDF files depends on the document, and we do not promise a figure. A report full of photos can shrink a great deal. A file that is mostly text will barely move.
One more thing: if you compress PDF files that carry a digital signature, the signature does not carry over into the copy.
The sites that compress PDF files for you need the file first, so the whole document goes to a server before a single byte is saved. Here the work is done in the browser tab or in the desktop app, and the smaller copy is written straight to your disk. OpenPdfEdit is an open source PDF editor, so you can check that in the code.
It is free to compress PDF documents in all three ways of running the app: the web app, the desktop app for macOS and Windows, and the extension for Chrome and Edge. No account is needed. If the copy is going to someone else, you can password protect a PDF afterwards, or merge PDF files first and compress the result once.
Compress PDF files in a browser tab: open the document, pick a level, save the smaller copy.
Guides: Two ways to save a PDF · All guides
Yes. Compression is free, with no account and no page limit. The only paid tools in the app are watermarking and OCR.
Partly. Text, fonts and line drawings are never changed. The Lossless level also keeps every pixel of every image, and saves less. Balanced and Smallest reduce image resolution, which is a loss. Balanced, at 150 dpi, stays sharp on screen and in office printing.
It depends on the document. Files full of high-resolution photos shrink the most. Files that are mostly text, or whose images are already small, change very little. We do not promise a ratio.
Start with Balanced, which keeps images sharp on screen and in office printing. If the copy is still too large, try Smallest, which is fine on screen and softer in print.
No. The document is read, compressed and saved on your own machine. No document, and no part of one, is sent anywhere.
Usually because it has few images, or its images are already at a low resolution, or they are in a format that is left untouched, such as JBIG2 or JPEG 2000. Text takes little space to begin with.