Make your PDFs
lighter without the compromise
Dial in exactly the quality you want — high compression for email attachments, balanced for sharing, near-lossless for archiving. Every byte of processing happens inside your browser tab. Nothing ever touches a server.
Drag the file onto the upload area or click to browse. The file is loaded directly into the browser's memory — no upload progress bar, because nothing leaves your device.
Choose High, Standard or Low, or drag the custom quality slider to a precise value. The preview updates in real time so you can judge the trade-off before committing.
Hit Compress PDF and save the output file. Close the tab and the browser releases its memory — nothing is retained, cached or logged.
Which compression level should you use?
The right setting depends on what is in the PDF and where it is going. Scanned documents, photo-heavy reports and text-only contracts all respond differently to compression. Here's a quick reference.
| Level | Typical size reduction | Best for | Avoid when | Recommended? |
|---|---|---|---|---|
| High Compression | 60 – 80% | Email attachments, web uploads, form submissions with strict limits | Documents with small-print text, fine diagrams or charts that need to stay sharp | For sharing |
| Standard | 30 – 50% | General-purpose use — client reports, invoices, slide exports | Almost never — this is the safe default for most use cases | Default pick |
| Low Compression | 10 – 25% | Archiving, print-ready files, PDFs you will edit or re-export later | When size is the primary concern — choose High instead | For quality |
Who actually needs this, and why
PDF compression is one of those tasks that sounds simple but catches people out in subtle ways. These four scenarios cover most of what comes up in practice.
Beating email attachment limits
Gmail caps attachments at 25 MB. Many HR portals and government forms top out at 5–10 MB. A scanned application pack can hit 30 MB without anyone trying. High compression usually brings it under the wire without making the text unreadable — and because the tool runs locally, there is no risk of uploading sensitive documents to a third-party server.
Sending client proofs without losing detail
High-resolution floor plans and rendered elevations can make a PDF enormous. Standard compression usually gets the file to an emailable size while keeping lines crisp enough for client review. Once approved, re-export from the source tool at full quality rather than compressing the already-compressed file — compression artefacts compound on re-save.
Uploading to submission portals
Turnitin, university portals and journal submission systems frequently impose a 20 MB limit. A thesis with embedded figures can easily exceed that. Compress with the Standard preset — it handles mixed text-and-image PDFs well and generally keeps references and footnotes readable at normal zoom levels.
Trimming product catalogues for download
A 200-page product catalogue with photography can run to 150 MB, which kills download conversion rates on slower connections. High compression at a custom quality of around 65 typically halves the file while keeping product photos recognisable. Pair this with a max-width resize of images before building the PDF for better results at any compression level.
Questions people actually ask
Straight answers about how the compression works, what changes in the output file, and what the tool cannot do.
Does compressing a PDF reduce its quality?
It depends on the preset. High compression is lossy — it re-encodes embedded images at a lower quality and can introduce subtle artefacts in photographs and gradients. Text and vector graphics are not degraded because they are stored as paths, not pixels.
Low compression makes only minor structural changes — removing redundant metadata, duplicate embedded resources and unused objects — so the rendered output is visually identical to the original at any zoom level.
Are my files uploaded to a server?
No. The tool runs entirely inside your browser using the JavaScript File API. There is no upload endpoint on this site — open your browser's Network tab while compressing a file and you will see zero outbound requests carrying your data.
This makes it safe for confidential documents: contracts, medical records, financial statements and anything else you would not want passing through a stranger's server.
Why is my compressed file still large?
A few common reasons: the PDF may be a scan of a physical document — in that case it consists entirely of high-resolution raster images, and only lossy compression makes a meaningful dent. If it was exported from a design tool like Illustrator, the file may contain embedded fonts that account for most of the size and cannot be stripped without breaking the document.
For scanned documents, High compression at a custom quality of 60–70 usually gives the largest reduction. For design exports, the most effective fix is to re-export at a lower DPI from the source application before compressing.
Will the compressed PDF still be searchable?
Yes, if the original was searchable. Compression here only targets embedded images and redundant metadata — the text layer and any existing OCR data are preserved untouched. A scanned PDF with no text layer will remain unsearchable after compression, just as it was before.
Is there a file size or page count limit?
No server-side quota — the only real limit is how much memory your browser allocates to the tab, which is typically several gigabytes on a modern desktop. Very large files (100 MB+) may cause the tab to pause briefly during processing; that is normal. For files over 200 MB, a desktop PDF application will generally be faster.
Continue your PDF workflow
Compression is usually one step in a longer chain. These tools handle what comes before and after — all running locally in your browser.
Combine multiple PDFs into one document and reorder pages before export. Compress the merged file in the same session.
Use tool → 🎨 PDF to ImagesExport every page as a PNG or JPEG. No page cap, no watermark. Useful when you need to compress individual pages separately.
Use tool → 🖼 Image CompressorShrink the source images before embedding them in a PDF to get better results than compressing the finished document alone.
Use tool → ❤️ iLovePDF ExternalCloud-based PDF suite with advanced compression algorithms. Note: files are uploaded to their servers, so weigh that against your privacy requirements.
Visit ilovepdf.com → 🅰 Adobe Acrobat Online ExternalAdobe's own cloud compressor. Produces excellent results for print-ready PDFs — requires a free Adobe account and uploads your file.
Visit adobe.com → 📄 Image to PDFTurn JPG, PNG or WebP images into a single clean PDF. Compress the output immediately in the same browser session.
Use tool →