Have you ever finished scanning your paperwork and tried uploading it to a job board, government website, or university portal, only to hit a wall?
A glaring red message stops you in your tracks: “File size exceeds the maximum limit of 5 MB.”
Modern desktop scanners and smartphone scanner apps capture documents in ultra-high resolution. A simple two-page or three-page scan can easily swell to 10 MB or 15 MB. When you try to email it, your email provider refuses the attachment, and web portals simply reject the upload.
While there are dozens of websites that offer to shrink PDFs online, uploading sensitive documents, such as tax returns, bank details, IDs, or medical records, to random internet servers poses a serious security risk.
With PDF Engine, you can optimize images and compress your PDF files directly on your Windows computer in seconds, keeping your private information 100% offline.
Step 1: Open PDF Engine and Choose “Merge PDFs”
Open PDF Engine on your computer:
- On the main welcome screen, click the Merge PDFs button.
Step 2: Select Your Documents
- Click the Browse folders… button in the top box.
- Select the PDF files you want to combine and optimize, then click Open.
- Your selected files will appear listed in the order box.
Step 3: Turn on the “Compress PDF” Switch
Right underneath the file list, you will find document optimization settings:
- Click the switch labeled Compress PDF to turn it on (it will highlight in green).
- (Optional) You can also select a standard page size from the dropdown menu (such as Letter or A4 Standard) to make sure all pages have uniform dimensions.
When this switch is active, PDF Engine automatically inspects large, heavy scanned images inside the document, resamples them to clean, web-friendly dimensions, and strips unnecessary digital overhead.
Step 4: Click “Merge PDFs”
- Click the large Merge PDFs button at the bottom.
- You will see the status change to show real-time progress:
- First, it unites the document pages.
- Then, it displays the live compression status:
Compressing... (X%).
Step 5: Check Your Size Savings
Once processing is complete, a confirmation box appears showing your exact results:
- It displays your Original size, your Final size, and the Percentage of reduction achieved (often between 40% and 70% smaller).
- Click the Open Folder button.
- Your newly compressed
merged_file.pdfis waiting inDownloads/pdf_engine/, ready to send by email or upload to any strict web portal without errors.
Your original files remain completely untouched on your hard drive, and you now have a lightweight, professional document ready for submission.