PDF & Image Compressor

Free PDF Compressor Online – Reduce PDF and Image Size

Upload limits on forms, email and cloud apps often reject oversized PDFs and photos. This PDF & Image Compressor on MooneyDesk helps you aim for a specific size in KB or MB. Processing is designed to stay in your browser using pdf.js, pdf-lib and the Canvas API—so files are not sent to MooneyDesk for compression.

How to compress a file

1. Add a file – Drag and drop or browse for a PDF or image (JPG, PNG, WebP).
2. Set the target – Enter a number and choose KB or MB (for example 50 KB, 100 KB or 1 MB).
3. Compress – Click Compress file and wait for the progress bar.
4. Download – Save the result. Original and new sizes are shown for comparison.

How PDF compression works here

Many “PDF compressors” re-render pages as images, then rebuild a new PDF. This tool follows that practical approach: it loads the document with pdf.js, draws each page at several resolutions, encodes page images as JPEG at different qualities, and embeds them with pdf-lib. That can shrink scanned or photo-heavy PDFs a lot. Text-only PDFs with few images may shrink less, because pure text is already efficient.

If the exact target cannot be reached without making the document unreadable, you get the smallest practical result the search found, with a clear warning.

Image compression

For images, the tool scales and adjusts JPEG quality to approach your target size. PNG/WebP inputs can be converted to a compact JPEG output when that better meets a strict KB limit (transparency may be flattened on white). For image-only workflows with more format options, you can also use the dedicated Image Compressor on MooneyDesk.

Common use cases

• Government, exam or job portals that require ID scans under 50–200 KB
• Email attachments that bounce above a fixed limit
• Course submissions and LMS uploads
• Shrinking multi-page scanned PDFs before sharing

Tips

• Start with a realistic target; extreme limits on high-resolution multi-page scans may need several attempts or lower expectations on sharpness.
• Keep the original file as backup.
• Very large PDFs depend on your device memory; close other heavy tabs if processing stalls.
• This is not password removal, OCR or PDF editing—only size reduction via re-rasterization for PDFs and canvas encode for images.

Privacy

Client-side libraries run in your browser. MooneyCourses does not operate a remote compress API for your document contents. Page assets (scripts, fonts) may load from CDNs; the selected file itself is processed locally for this tool’s workflow.

Limitations

Quality always involves a trade-off. Vector text may become image-based after PDF re-render. Exact byte targets are not always possible. Browser differences can affect speed. For mission-critical print masters, prefer professional desktop tools and keep originals.

Use the dark mode control in the header for low-light sessions. Compress free, without an account, on MooneyDesk.