Your files are processed in the browser. Toolmivo does not need to upload them to a conversion server.
PDF tools
Compress PDF Online
Reduce the size of image-heavy or scanned PDFs with adjustable compression. The document is processed locally in your browser.
Compress PDF
Choose one PDF and select a compression level.
🔒 Browser processing
Drop a PDF here or click to browse
PDF only • best for scanned and image-heavy PDFs
Compression
This browser-based compressor rasterises PDF pages. Text selection, forms and interactive elements are not preserved.
Simple controls, clear progress and direct downloads without creating an account.
Designed for current Chrome, Edge, Firefox and Safari versions on desktop and mobile.
Best results are usually achieved with scanned or image-heavy PDFs. Text-heavy PDFs can occasionally become larger.
About the tool
What does PDF compression do?
PDF compression reduces the amount of data needed to store a document. This can make a file easier to upload, attach to an email, archive or transfer between devices. Toolmivo is designed primarily for scanned and image-heavy PDFs, where page images often account for most of the file size.
Before compression
A scanned document may contain full-resolution page images that make the PDF much larger than necessary for normal viewing.
Example: scanned document with high-resolution page images
After compression
The pages are rebuilt with more compact image data according to the selected compression level.
Result: smaller PDF when the source is suitable for raster compression
How it works
How Toolmivo compresses PDF files
This compressor uses a browser-based rasterisation workflow. Each PDF page is rendered in the browser and then added to a new PDF using compressed image data. This approach can reduce the size of scans and image-heavy documents, but it behaves differently from low-level optimisation tools that rewrite existing PDF objects.
- The PDF is opened in your browser.
- Each page is rendered as visual page content.
- The selected compression level controls the image-quality trade-off.
- A new PDF is created from the processed pages.
- You can compare the original and result sizes before downloading.
Important: because pages are rasterised, searchable/selectable text, PDF forms, interactive fields and other embedded elements are not preserved in the rebuilt file. Use the original PDF when those features matter.
Compression levels
Which compression level should you choose?
Higher compression usually produces a smaller file but can reduce image sharpness. The best setting depends on whether file size or visual quality matters more.
Strong — smallest file
Best when reducing file size is the main priority. Fine details and small scanned text can become softer, so review the result before using it for important documents.
Balanced — recommended
A practical default for many scanned documents. It aims to reduce size while keeping the pages reasonably clear for everyday viewing.
High quality — larger file
Keeps more visual detail and is useful when the document contains diagrams, photos or small text that should remain as clear as possible.
Always compare the result
Compression savings depend on the source PDF. Check both the new file size and page quality before deleting or replacing the original document.
Best candidates
Which PDFs usually compress well?
Scanned paperwork
Multi-page scans often contain large page images and can benefit noticeably from image recompression.
Photo-heavy PDFs
Documents built from photos or screenshots can contain much more image data than is needed for normal screen viewing.
PDFs made from image scans
Receipts, forms, notes and archived paper documents are common candidates for this type of browser-based compression.
Email attachments
A smaller version can be more convenient when a mail provider or recipient has attachment-size restrictions.
Upload portals
Some applications, support systems and document portals set maximum upload sizes. Compression can help when the original scan exceeds the limit.
Archive copies
Smaller viewing copies can save storage space when the original high-quality document is kept separately.
When not to use it
When this compressor may not be the best choice
Raster-based compression is useful for some PDFs but not every PDF. A text-heavy digital document may already store its text and graphics very efficiently. Rebuilding every page as an image can remove useful PDF features and can sometimes increase rather than reduce the total file size.
- Searchable text matters: keep the original if users need to search or select text.
- Forms or interactive fields matter: rasterisation does not preserve them.
- The PDF contains clickable links: those interactive elements are not retained.
- The PDF is already small: additional rasterisation may offer little benefit.
- The document is mainly vector text and graphics: the result can be larger than the source.
How to use it
How to compress a PDF with Toolmivo
- Add one PDF using the drop zone or file browser.
- Choose a compression level based on the balance you want between quality and file size.
- Click Compress PDF to start browser-based processing.
- Watch the progress indicator while the pages are processed.
- Compare Original, Result and Change before downloading.
- Open the downloaded PDF and check page quality before replacing the source file.
File size
Why some PDFs become smaller than others
PDF size depends on what the document contains. A scanned page may be almost entirely image data, while a digitally generated report may consist mostly of compact text, fonts and vector graphics. Recompressing page images can create large savings in the first case and little or no savings in the second. The original image resolution, page count, colour detail and existing PDF optimisation all affect the final result.
Image-heavy source
High-resolution scans and photos usually offer more data that can be reduced.
Text-heavy source
Digitally generated text PDFs may already be compact, so rebuilding pages as images can sometimes make the file larger.
Quality and readability
How compression affects PDF quality
Stronger compression reduces image data, which can soften edges and remove fine detail. That may be acceptable for simple scans viewed on screen, but it can be noticeable in small fonts, diagrams, signatures and photographs. If readability is more important than maximum file reduction, start with Balanced or High quality and inspect the output before trying Strong compression.
For important records: keep the original PDF. A compressed copy is useful for sharing or uploading, but the original should remain available when you need the highest quality or original PDF structure.
Privacy
Browser-based PDF processing
The compression workflow is performed in your browser. Toolmivo does not need to send the selected document to a separate conversion server for this tool to perform the compression. Processing speed depends on the device, browser, PDF page count and page complexity, so large documents may use more memory and take longer to finish.
Related tools
More Toolmivo PDF tools
Depending on what you need to do with the document, you can convert images to PDF, export PDF pages as images, combine documents or extract selected pages.
FAQ
Compress PDF FAQ
How does Toolmivo compress a PDF?
The tool renders each PDF page in the browser and rebuilds the document using compressed page images. This is particularly useful for scanned and image-heavy PDFs.
What PDFs work best with this compressor?
Scanned documents, photo-heavy PDFs and PDFs made from page images usually benefit most. Text-heavy digital PDFs may see little reduction.
Will searchable text still work?
No. Because the pages are rasterised, searchable and selectable text is not preserved in the rebuilt PDF.
Are PDF forms and interactive elements preserved?
No. Forms, interactive fields and similar PDF features are not preserved by this raster-based compression workflow.
Can a compressed PDF become larger?
Yes. If the original PDF already stores text and graphics efficiently, converting every page into image content can make the result larger than the source.
Which compression setting should I choose?
Balanced is a practical default. Use Strong when file size is the main priority, or High quality when page detail matters more.
Does Toolmivo upload the PDF to a conversion server?
The compression process runs locally in your browser and does not require the document to be uploaded to a conversion server.
Why can large PDFs take longer?
Each page must be rendered and processed. Documents with many pages, large scans or complex page content require more browser memory and processing time.
Should I keep the original PDF?
Yes, especially for important documents. The compressed file is useful for sharing and uploading, while the original preserves maximum quality and the original PDF structure.