Compress PDF Files Online
Reduce PDF size in a few clicks. Add one PDF or select multiple files, choose a compression level, and download the smaller files.
Drop your PDF files here
or choose files from your computer · Multiple PDFs supported
How to compress a PDF
Upload one file or select several PDFs at once. Files are processed locally in your browser.
Use Recommended for balance or Strong when reducing size matters more than image detail.
Check each result's size and reduction, then download individual PDFs or a ZIP bundle.
Free Online PDF Compressor – Reduce PDF File Size
Need to email a document, upload an application, or share a PDF that is too large? FreeKitTools helps you compress PDF files online for free with a straightforward workflow. Select a PDF from your device, choose a compression level, and process the file in your browser. You can work with one PDF or select several files together, then download each finished PDF individually. When you have compressed multiple documents, a ZIP download is also available to make collecting the files easier.
Choose the right PDF compression level
Different documents need different settings. The Light option uses higher image detail and may be useful when readability is the priority. Recommended aims to balance visual quality and file size for everyday sharing. Strong uses lower image resolution and stronger JPEG compression to target a smaller output, which may make tiny text or photographs look softer. Results depend on the original PDF: image-heavy scans often have more room for size reduction than a PDF that is already optimized. No online tool can guarantee the same percentage reduction for every document.
Compress one PDF or multiple PDF files
Use the file picker or drag and drop your PDFs into the upload area. After selection, review the file names and original sizes before starting. Once processing finishes, each file shows its result and has its own Download PDF button, so you do not need to download a ZIP just to get one document. If you processed more than one PDF successfully, use Download all as ZIP to collect the results together. If a compressed result is larger than the original and the keep-original option is enabled, the tool keeps the original file instead.
Private, browser-based PDF compression
Your selected PDF contents are processed locally in your browser rather than uploaded to the FreeKitTools website. The page loads its PDF processing libraries from public content-delivery networks, so an internet connection is needed to open those libraries. Large files or PDFs with many pages can use substantial memory and may take longer on older devices. For smoother processing, close unused browser tabs and try a lighter setting if a file is especially large.
Important information about PDF quality and text
This compressor reduces size by rendering PDF pages as images and rebuilding the document. It is therefore best suited to scanned pages and documents where a smaller visual copy is the main goal. In the output, text may no longer be selectable, searchable, or accessible to screen readers; vector graphics can lose their crispness when zoomed in. Forms, interactive elements, digital signatures, bookmarks, accessibility structure, and other advanced PDF features may not be preserved. If you need to edit text later, verify signatures, or keep a searchable archive, retain the original PDF and consider a compression method that preserves the document's internal structure.
Whether you call it a PDF size reducer, PDF optimizer, or PDF compressor, the best setting depends on how you plan to use the file. Always compare the output with the original before sharing an important document, and keep a backup of your original PDF.
Frequently asked questions
Will the PDF always become smaller?
No. Results depend on the original PDF. Image-heavy or scanned PDFs usually benefit most. If the output is larger, the default option keeps your original file instead.
Can I still select or search text after compression?
This image-based compression method turns each page into an image, so text is generally no longer selectable or searchable. Keep the original if searchable text matters.
Are my files uploaded to FreeKitTools?
No. This page reads and processes files in your browser. It does not send the PDF contents to FreeKitTools' server. The PDF processing libraries load from public CDNs.
Can I compress multiple PDFs together?
Yes. Select multiple files, run compression, then download each result separately or use Download all as ZIP.