Compress PDF
Reduce PDF file size with lossless or image-based compression options in your browser.
PRACTICAL WORKFLOW NOTES
Choose the Compression Method That Fits the Document
Reducing a PDF is not always the same job. A scanned packet may be dominated by large page images, while a digitally created document may depend on searchable text, vectors, links, forms, and other PDF objects that should remain intact. Choosing the compression mode according to the document is more useful than chasing the smallest number without checking what changed. Compress PDF provides image-based Balanced, Strong, and Maximum modes as well as a Lossless option. The image-based modes rebuild pages as compressed images and can be effective for scans or photo-heavy PDFs. Lossless keeps the PDF structure and is the safer choice when selectable text, links, vectors, forms, or page objects are important, although the size reduction may be smaller.
For scan-heavy or photo-heavy PDFs, start with Balanced and inspect the result before moving to Strong or Maximum. Those stronger modes trade progressively more rendered detail for a smaller image-based document. Choose Lossless instead when preserving selectable text, vector graphics, links, forms, and the original PDF object structure matters more than obtaining the smallest possible file. This mode-by-mode decision is more reliable than applying one compression level to every document type.
A useful compression check has two parts: file size and document behavior. Compare the result size with the source, then open several representative pages at normal reading zoom. If you used an image-based mode, look closely at small text, diagrams, signatures, and photographs. If you used Lossless, confirm that the document still behaves as expected and remember that an already optimized PDF may have little redundant data left to remove.
Compression runs on your device, so large scans and long documents can use substantial browser memory while the job is active. There is no fixed page-count limit in the current workflow; practical speed and capacity depend on the browser, available memory, and the document itself. Keep the original PDF until the compressed result has been reviewed. If the real task is to combine several documents first, merge them before compression so you can evaluate one final file instead of several unrelated outputs.
How to Compress a PDF Online
Choose the compression method before the browser rebuilds or optimizes the document.
Add your PDFs
Select one or more PDF files. There is no fixed page-count limit; larger documents can take longer because processing runs locally in your browser.
Choose a compression level
Start with Balanced, move to Strong or Maximum when a smaller file matters more, or use Lossless when document structure must be preserved.
Choose color or grayscale
Image-based modes can keep the original colors or convert pages to grayscale. Grayscale can help shrink scanned or color-heavy PDFs further.
Name the outputs
Keep the default -compressed suffix or enter your own suffix so the new file is easy to distinguish from the source.
Compress and review
Preview or download each result. When several PDFs finish successfully, download them together as a ZIP.
PAGE INSPECTOR
Inspect pages before processing
Use Open pages on any uploaded PDF to inspect and organize its pages before this tool processes the file. If several PDFs are in the queue, each file can be opened and prepared independently.
Preview pages clearly
Open a larger preview when thumbnails are not enough to identify similar pages or scanned frames.
Rotate before processing
Rotate individual pages left or right. The selected orientation is carried into the working copy used by the tool.
Delete, restore, or reset
Temporarily remove unwanted pages, restore deleted pages, or reset the file back to its original page state before continuing.
Drag pages into a new order
Reorder pages or TIFF frames by dragging their cards. Your original upload stays unchanged; the tool processes the resulting working copy.
Which PDF Compression Level Should You Use?
The four modes are intentionally different because there is no single best way to reduce every PDF.
Balanced
The recommended starting point for ordinary scans and image-heavy PDFs. It aims for a useful size reduction while keeping pages comfortable to read on screen.
Strong
Uses a lighter page render and stronger JPG compression than Balanced. Choose it when the file still needs to be smaller and some image detail can be reduced.
Maximum
Prioritizes the smallest output among the image-based presets. It is intended for screen viewing and sharing where compact size matters more than fine detail.
Lossless
Preserves selectable text, vector content, links, forms, and page structure. It is the right choice when you want to reduce PDF size without flattening the document, although the size saving may be limited.
What Actually Happens When the PDF Gets Smaller?
The important difference is whether the page remains a structured PDF page or becomes a compressed page image.
Scans usually benefit most
Scanned documents and PDFs filled with photographs often contain large image data. Image-based compression can reduce those files much more than a structure-only rewrite.
Searchable text is a mode choice
Balanced, Strong, and Maximum flatten each page into an image. Lossless keeps the text layer and other PDF objects instead.
Grayscale can remove unnecessary color data
For black-and-white paperwork, invoices, forms, and scanned letters, grayscale may reduce file size without needing the color information in the source.
An already optimized PDF may not shrink
The tool compares the generated file with the original. If the candidate would be larger, the result keeps the original PDF data rather than replacing it with a larger file.
Multiple files stay separate
Compressing several PDFs does not merge them. Each input creates its own result, and successful results can also be downloaded together as a ZIP.
Browser resources still matter
The work runs on your device. Large scans and high page counts can use substantial memory, so processing speed depends on the browser and device.
Use the Right PDF Tool for the Real Problem
Sometimes reducing image quality is not the best way to make a document easier to send or manage.
Merge PDF
Combine several documents first, then compress the finished PDF when you need one smaller file for sharing or upload.
Split PDF
Separate a long PDF when the real goal is to send only one section instead of lowering the quality of the whole document.
Delete PDF Pages
Remove pages you do not need before compression when unnecessary content is contributing to the file size.
PDF to JPG
Export pages as images instead when the recipient does not need a PDF document and individual JPG pages are more useful.
PRIVACY & RESPONSIBLE USE
Your PDF Is Processed in the Browser
The current Compress PDF workflow reads and processes the selected PDF contents on your device and does not create a server-side document copy for the compression operation. Large files remain subject to the memory and performance limits of the active browser session.
See File Security & Processing and the Privacy Policy for broader site-level details.
Compression changes the output file
The downloaded result is a new PDF. Image-based modes intentionally flatten page content, while Lossless mode preserves the original PDF structure as far as the optimization process allows.
Use documents you may process
Compress files you created, own, are licensed to use, have permission to process, or may otherwise use lawfully.
No password or protection bypass
The tool does not bypass passwords, encryption, DRM, copying restrictions, or other document protections.
Copyright: Reducing PDF size does not transfer ownership, remove attribution duties, or create permission to distribute protected material. See Copyright & Intellectual Property for the full site notice.
COMMON QUESTIONS
Frequently Asked Questions About Compressing PDF Files
Can I compress a PDF online for free?
Yes. The current Compress PDF tool is free to use and does not require an account. Add one or more PDFs, choose a compression mode, and download the results from the same browser workspace.
Which PDF compression level should I choose?
Balanced is the general-purpose starting point for scans and image-heavy PDFs. Strong reduces image detail further, Maximum prioritizes the smallest file, and Lossless preserves searchable text, vectors, links, forms, and page structure.
Can I reduce PDF size without losing searchable text?
Use Lossless mode when searchable text and document structure must remain intact. File-size reduction can be limited on PDFs that are already optimized. Balanced, Strong, and Maximum rebuild pages as images and therefore flatten searchable text, links, forms, and layers.
Can I compress multiple PDF files at once?
Yes. Add multiple PDFs and receive a separate compressed result for each file. There is no fixed page-count limit; practical speed depends on browser memory and device performance.
Can grayscale make a PDF smaller?
Often, yes. Grayscale is available with the image-based compression levels and can reduce file size for scanned or color-heavy documents. It is disabled in Lossless mode because that mode preserves the original document structure.
What happens when the compressed PDF would be larger?
The tool compares the generated candidate with the source file. If the candidate would be larger, the result keeps the original PDF data instead of replacing it with a larger version.
Can I download several compressed PDFs together?
Yes. Preview or download each compressed PDF separately, or download multiple successful results together as a ZIP file.
Are my PDF files uploaded to a server for compression?
The current Compress PDF workflow processes the selected PDF contents in your browser and does not create a server-side document copy for the compression operation.
Can Compress PDF bypass a password or document restriction?
No. The tool does not bypass passwords, encryption, DRM, or document restrictions. Use a PDF you are authorized to open and process.
Compress PDF
Reduce PDF file size with lossless or image-based compression.