TL;DR: Upload a PDF, pick a compression level (Light / Recommended / Extreme), and download the smaller version — typically 50-75% smaller.
Compress PDF online for free — reduce PDF file size by up to 90% without losing quality. Choose from light, balanced, or extreme compression levels. Preview estimated savings before downloading. No file limits, no sign-up.
Reach for Compress PDF when you want the job done without handing your file to a data broker. Browser-native tools stay on your device; the rest use a single-request isolated container that deletes the file right after responding. MIT-licensed and ad-free.
Compress PDF online for free — reduce PDF file size by up to 90% without losing quality. Choose from light, balanced, or extreme compression levels. Preview estimated savings before downloading. No file limits, no sign-up. Use it when you need a quick, private, no-account way to handle a pdf in the browser, or when you want an auditable open-source alternative to iLovePDF, Smallpdf, Adobe Acrobat, PDF24, and Sejda. The page at /tool/compress-pdf is designed for one clear job: upload or provide the input, choose only the options that matter, and download the result without creating an account or passing through a sales funnel.
PDF operations that need server-side libraries run inside the PrivaTools container and return a fresh download; browser-only PDF helpers stay on-device. Temporary input and output files are not used for analytics, model training, advertising profiles, or product telemetry. The public demo uses anonymous page-view analytics only; file bytes, extracted text, filenames, passwords, signatures, and generated results are outside that analytics path. If your organization needs stricter controls, you can self-host all 214 PrivaTools utilities and keep processing on your own infrastructure.
Before running Compress PDF, confirm that the source file opens correctly and that you have permission to process it. Keep an untouched original, run one operation at a time when quality matters, and use Pipeline when you want repeatable multi-step output. For sensitive material, review the downloaded result before sharing it. For large files, give the browser time to finish the download and avoid refreshing the page mid-run. If a password, damaged upload, unsupported codec, or malformed document blocks processing, PrivaTools returns a plain-language error so you can pick the next recovery step instead of guessing.
Compress PDF is intentionally narrow: it does one pdf task and hands the result back as a normal download. That makes the output easy to inspect, rename, archive, attach to email, or feed into another tool. If you need a repeatable workflow, save the page, bookmark a Pipeline recipe, or self-host the API so the same steps can run from internal scripts. The interface avoids accounts and cloud folders on purpose: the safest default for private files is to process only the current request, return the result, and leave long-term storage under your control.
Compress PDF runs in any modern browser on Windows, macOS, Linux, Android, and iOS — there is nothing to install, no extension to add, and no desktop app to keep updated. Because the interface is a single page, you can bookmark it, send the link to a colleague, or open it on a phone and get the same result you would on a laptop. There are no watermarks stamped onto your output, no sign-in wall before the download, and no paid tier that unlocks the “real” version later — the Compress PDF you see is the complete tool. For teams that would rather keep everything in-house, the same endpoint ships in the MIT-licensed, self-hostable build, so you can run it behind your own firewall with identical behaviour and no outbound calls. That combination — instant in the browser for individuals, fully self-hostable for organizations — is what keeps a private file genuinely private from upload to download.
Most PDFs shrink 50–75%. Scanned PDFs with large embedded images often see 70–90% reduction; text-heavy PDFs with vector graphics may only shrink 5–15% because the text is already minimally encoded.
Text and vector graphics are always lossless — you cannot tell them apart from the original. Only embedded raster images are recompressed, and only at the Recommended or Extreme presets. Use the Light preset to keep images untouched.
Yes. The compressed file is processed in an isolated Docker container, held in temporary per-request storage for the duration of the request, and unlinked the moment the response is delivered. The file is never written to permanent storage, never logged, and never used to train any model. The entire stack is open source so you can verify this on GitHub.
500 MB per file. There is no daily, weekly, or monthly quota — you can compress unlimited files. If you need to compress dozens of files at once, use the Batch Compress PDF tool which accepts up to 50 PDFs in one go.
Not directly — encryption prevents the compressor from rewriting the content streams. Use the Unlock PDF tool first (you'll need the password), compress the unlocked version, then re-protect with the Protect PDF tool if needed.
Free with no daily quota (iLovePDF and Smallpdf cap free tier at 2 files/day), no watermark, no account required, no file size limit beyond 500 MB, and the entire compressor is open source under the MIT license so you can self-host it.
See how PrivaTools compares to iLovePDF, Smallpdf, Adobe Acrobat, and other free PDF tools.