Optimize PDF
Try reducing PDF size by re-saving with object streams, without intentionally rasterizing pages or recompressing images. Savings vary; keep the original and check the output. Free, private, in your browser.
Files processed in your browserSelect a PDF or drag & drop
One PDF, up to 100 MB
Your files never leave your device. Optimize PDF runs entirely in your browser using JavaScript. Nothing is uploaded to a server. When you close this tab, your file is gone from memory.
How to optimize pdf
- Select your PDF. Choose or drag in the PDF you want to streamline.
- Optimize. Press Optimize PDF. The document is re-saved with object streams in your browser.
- Download. Download the smaller file, then validate it and keep the original, especially for signatures, forms or PDF/A files.
Want more detail? Read our full guide: How to optimize a PDF.
Why optimize a PDF?
PDF size depends on more than the visible pages. Some editors append incremental saves, and some writers store objects less compactly than others. That overhead can make a file harder to attach or slower to transfer even when its pages look simple. Re-saving with a different structure may help, but not every large file has structural savings available.
This tool loads the PDF and saves it with object streams enabled. It does not intentionally turn pages into images or recompress embedded pictures. This makes it worth trying when you want to avoid deliberate rasterization, but it is not a promise that every PDF feature will survive the rewrite unchanged. Keep an original and check text, links, forms and the appearance of the downloaded copy.
Savings depend on the source document. Large photos and scans may dominate its size, and this rewrite does not reduce their resolution. The tool only offers a download if it achieves at least a 2% reduction. A smaller saving means this method did not help enough, not that all possible optimization has been tried.
Processing happens in your browser without uploading the file. That does not make the result an archival or sanitization pass: unused objects and duplicate resources are not comprehensively scrubbed. Rewriting can invalidate digital signatures or affect form behavior and PDF/A conformance. Use the required validation tools before relying on a copy for signed or archival records.
Frequently asked questions
Are my files uploaded?
No. The optimization runs entirely in your browser, so the file is not uploaded for processing.
What's the difference between Optimize and Compress?
Optimize re-saves the PDF with object streams without intentionally rasterizing pages or recompressing images. Compress renders pages as images, which may save more space but loses text selection and can lose interactive features. Neither is a substitute for checking the output against your requirements.
Why would a PDF be bigger than it needs to be?
An editor may append incremental saves, or a PDF writer may not use compact object streams. Re-saving can reduce some structural overhead, but this tool does not promise to remove every unused object, merge duplicate resources or erase editing history.
Will anything look different?
The tool does not intentionally rasterize or recompress content, but a PDF rewrite is not a guarantee that every feature is preserved. Keep the original and validate the saved PDF, especially if it has signatures, forms or PDF/A requirements.
What if my PDF doesn't get smaller?
The tool offers a download only when this rewrite reduces size by at least 2%. A smaller saving does not prove the file is fully optimized. If large images are the issue, consider Compress only if its quality and feature trade-offs suit your document.