Compress PDF
Reduce the file size of a PDF for free so it's small enough to email or upload — entirely in your browser. Your file is never uploaded to a server.
How to compress a PDF
- Open the Compress tool and add your PDF — drag and drop it, or click “Choose files.”
- Pick a level. Choose Light (best quality), Recommended (a good balance), or Maximum (smallest file).
- Compress & download. The smaller PDF is generated on your device and saved to your Downloads folder.
Shrink PDFs without uploading them
Most “compress PDF” websites upload your document to their servers to process it. LambiPdf compresses PDFs using your own browser, so sensitive contracts, scans, and reports never leave your computer. It's free, needs no account, and adds no watermark. Compression re-renders each page at a lower resolution, which is ideal for scanned or image-heavy PDFs that are too large to send.
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Compress PDF — FAQ
Is compressing PDFs on LambiPdf free?
Yes — it's completely free, with no sign-up and no watermark.
Are my files uploaded when I compress?
No. Compression happens entirely in your browser; your file never leaves your device.
How much smaller will my PDF get?
It depends on the file and the level you choose. Scanned or image-heavy PDFs shrink the most; the Maximum level gives the smallest file.
Will the text still be selectable after compressing?
Compression re-renders pages as images, so text becomes part of the page image. If you need selectable text afterwards, use the OCR tool.