PDF Compressor

About PDF Compressor

PDF compression matters more than most people realize. A scanned ID document might be 8 MB. An emailed salary slip with embedded images could be 15 MB. Many government portals in India — eSampark, DigiLocker, e-District, the EPFO UAN portal — have strict file size limits, often between 500 KB and 2 MB. Emailing large PDFs eats through Gmail's 25 MB attachment limit quickly. WhatsApp caps document shares at 100 MB, but people prefer smaller files for faster delivery on mobile connections.

This PDF compressor reduces file size by restructuring the PDF's internal format — removing unused metadata, optimizing object streams, and applying lossless compression to content streams. Three compression levels let you balance quality preservation against maximum size reduction. All processing runs entirely in your browser using pdf-lib. Nothing is uploaded anywhere.

How to Use the PDF Compressor

1. Upload your PDF by clicking or dragging it to the upload area.
2. Select a compression level: Low (best quality, moderate size reduction), Medium (balanced), or High (maximum compression).
3. Click "Compress PDF" and wait for processing — a progress bar tracks each page.
4. Review the before/after file size comparison shown in the result.
5. Download the compressed PDF. If the reduction isn't sufficient, try a higher level.

Start with Low compression — it removes most overhead without touching content quality. Only switch to High if you need the absolute smallest file size and can accept some trade-offs in how embedded data is handled.

Common Use Cases

• Government portal uploads: State government portals often cap uploads at 500 KB or 1 MB. Compress your scanned certificates, mark sheets, or income proof PDFs before submitting on portals like Samagra, e-District, UPSC, or the EPFO UAN portal.
• Email attachments: Compress multi-page PDFs before sending when you're close to the 25 MB Gmail attachment limit. A compressed proposal or report is also faster to download for the recipient on a mobile connection.
• WhatsApp document sharing: Sending a 10 MB PDF to a group or client? Compress it to under 2 MB for near-instant delivery, even on slower 4G connections.
• Cloud storage management: If you maintain a Google Drive or OneDrive folder of scanned documents, compressing before uploading saves meaningful storage across hundreds of documents over time.

Tips for Best Results

• Try "Low" compression first — it preserves quality perfectly and still removes most wasted overhead from typical PDFs generated by office software.
• PDFs made primarily from text (reports, bank statements, Word-exported documents) compress far better than scan-heavy PDFs full of images.
• If you need to compress a scan-heavy PDF significantly, compress the source images using the Image Compressor first, then create a fresh PDF using Image to PDF.
• After compression, open the output PDF to verify quality before submitting anywhere critical — especially government or financial portals.

Why Use PDF Compressor on OurTools.in

Online PDF compressors that require server uploads have real downsides: your file travels to a third-party server, waits in a queue, gets processed, and is held temporarily. For documents like salary slips, Aadhaar copies, medical reports, or property documents, this is a genuine privacy concern. This tool does everything locally in your browser. The compression uses pdf-lib to rebuild the PDF structure without any round-trip to a server.

There are no limits — no daily compression quota, no maximum file size enforced by a paywall, no watermark stamped on your result. The tool shows you the before/after size comparison so you know exactly how effective the compression was before downloading. Free, private, and browser-based.

Limitations to Know About

This tool compresses by restructuring the PDF's internal streams — it does not re-encode embedded images to lower quality. Scanned PDFs that are mostly large images may see modest reductions (typically 10–30%). PDFs already optimized by Adobe Acrobat or a previous compression pass will see smaller gains. If you need to aggressively compress a scan-heavy PDF, use Image to PDF after compressing the source images individually. Very large PDFs (150 MB+) may take time and consume significant browser memory — close other tabs for best performance.