Reduce PDF file size while maintaining quality. Advanced optimization options for faster sharing and storage. Free online PDF compressor.
Compress PDF in a few steps
- 1
Open Compress PDF and drag your file into the upload area, or click to browse from your device.
- 2
Adjust the available options to match what you need.
- 3
Run the tool — all processing happens locally, in your browser, in seconds.
- 4
Download the result. Your original file is never modified or uploaded.
What Compress PDF is good for
Private, sensitive documents
Contracts, IDs, medical records and financial statements should not be uploaded to a stranger's server. With Compress PDF, they never leave your device.
Working offline or on the move
On a plane, on a train, or behind a strict firewall — Compress PDF keeps working without a connection once loaded.
Quick, repeatable tasks
No accounts, no installs, no daily limits. Open the page, get the job done, and close the tab.
Frequently asked questions
- Will compression reduce the quality of my PDF?
- Compression trades some image fidelity for a smaller file. You can choose a compression level to balance size against quality, and text remains crisp.
- How small can the file get?
- It depends on the content — image-heavy PDFs shrink the most, while text-only PDFs are already compact. The tool shows the before-and-after size for every file.
- Is Compress PDF free to use?
- Yes. Compress PDF is completely free, with no sign-up, watermarks, daily quotas, or file-size caps. You can process as many files as your device can handle.
- Are my files uploaded to a server?
- No. Compress PDF runs entirely in your browser using WebAssembly. Your documents never leave your device — there are no uploads, no servers, and nothing is stored or logged. That is what makes PDF-Atlas private by architecture.
- Does Compress PDF work offline?
- Yes. After the page has loaded once, the tool keeps working without an internet connection. You can also install PDF-Atlas as a desktop app or PWA for a fully offline experience.
- Is my data safe?
- Because all processing happens locally on your machine, your files are as safe as the device they sit on. Nothing is transmitted to PDF-Atlas or any third party.