PDFMasterCompress PDF
Reduce the file size with four quality presets or a target size from 100 KB to 10 MB.
3 free files a day · No sign-up · No ads
Frequently asked questions
How do I compress a PDF online for free?
Upload the file to Compress PDF, pick a compression level or a target size and press Run. The tool re-encodes images and fonts on our servers and returns a smaller PDF with the new size shown next to the old one. It is free for 3 files a day, with no account and no ads.
How do I compress a PDF to under 1 MB?
Choose 1 MB in the target size selector and run the tool. PDFMaster tries increasingly stronger compression until the result fits under 1 MB; if the document cannot get that small, you receive the smallest version it could produce and a notice with the size reached. Scanned and image-heavy PDFs shrink the most, while text-only PDFs are often already under 1 MB.
Can I compress a PDF to 100 KB or 200 KB?
Yes, the target size selector goes down to 100 KB, with 200 KB and 500 KB in between. Reaching sizes that small means images are reduced to screen resolution, so a photo-heavy PDF may look soft and a long scan may not get there at all; in that case the tool returns its smallest result and tells you. Splitting the PDF first is the usual fix when the target comes from an upload form.
How do I compress a PDF without losing quality?
Pick High quality (print) or Best quality (prepress): text stays sharp and vector, and images keep print resolution, so the reduction comes from removing duplicate objects, unused data and heavier encodings. The file shrinks less than with Maximum (screen), but the pages look the same on paper. For screen reading, Balanced (ebook) keeps 150 dpi images, which is usually indistinguishable on a monitor or phone.
What do the compression levels mean?
Maximum (screen) targets on-screen viewing with 72 dpi images and gives the smallest file; Balanced (ebook) keeps 150 dpi and is the default for email and sharing; High quality (print) keeps 300 dpi for printing; Best quality (prepress) also preserves colour profiles for professional printing. If you would rather set a size than a level, use the target size selector and the tool picks the level for you.
Is compressing a PDF free, and is there a daily limit?
Yes. Everyone gets 3 files a day for free without creating an account, and the counter resets daily; Premium covers heavier use. There are no ads and no watermark on the compressed file.
Is it safe to upload my PDF to compress it?
The file goes over HTTPS, is compressed on our servers and is deleted with the result as soon as the job ends. We never read, index or share your documents. Once you download the result, nothing remains on our side.
Why did my PDF barely shrink after compressing?
Compression works mainly by re-encoding images, so a PDF that is mostly text, vector graphics or already optimized images has little to give. Pick Maximum (screen) or a lower target size to force stronger image downsampling, or split the document into parts if a hard size limit is the problem. A PDF that grew after compression usually held images in a format that recompresses badly, so keep the original in that case.