Method 1 — Compress the PDF (fastest)
The quickest way to reduce PDF size is to use a compression tool. This works by reducing the resolution of images embedded in the PDF — the main cause of large file sizes.
Go to Bisnep PDF Compress tool
Open bisnep.com/compress-pdf-quality in your browser.
Upload your PDF
Drop the file or click browse. Your file never leaves your browser.
Download the smaller PDF
Choose your quality level and download. Done in seconds.
Best for: PDFs with photos or scanned pages. Can reduce file size by 50–90%.
Method 2 — Convert to greyscale
Colour information takes up a lot of space. If your PDF doesn't need to be in colour — for example, a text report with some charts — converting it to greyscale can noticeably reduce the file size.
Use the PDF to Greyscale tool to instantly convert your colour PDF to black and white.
Best for: Reports, scanned documents, forms. Typical reduction: 20–40%.
Method 3 — Delete unnecessary pages
If your PDF has blank pages, duplicate pages, or sections you don't need, removing them reduces the file size proportionally. A 20-page PDF that becomes a 15-page PDF is automatically 25% smaller.
Use the Delete Pages tool to remove any unwanted pages.
Best for: Documents with blank pages or unused sections.
Method 4 — Split and send only what you need
If you only need to send part of a PDF — say, pages 3 to 8 of a 30-page document — splitting it first means sending a much smaller file. The recipient gets exactly what they need.
Use the Split PDF tool to extract specific pages into a new, smaller PDF.
Best for: When you only need to share a portion of a large document.
Method 5 — Crop oversized margins
PDFs generated from certain software sometimes have very large margins or blank space around the content. Cropping the page to remove this whitespace can reduce file size, particularly in PDFs with many pages.
Use the Crop PDF Margins tool to trim excess whitespace from every page.
Best for: PDFs exported from presentation software or scanned with large white borders.
Start with Method 1 (compression). If the result is still too large, combine it with Method 2 (greyscale) or Method 3 (delete pages). For most people, compression alone reduces the file size enough to send by email.
How small do I need my PDF to be?
| Use Case | Target Size |
|---|---|
| Gmail / Outlook email attachment | Under 25MB |
| WhatsApp file sharing | Under 100MB |
| Most web upload forms / portals | Under 10MB |
| LinkedIn or job application portals | Under 5MB |
| Printing (keeping quality) | Any size is fine |
Every tool listed above processes your PDF in your browser. Your file is never uploaded to any server, so your documents stay completely private — even sensitive files like financial reports or contracts.