Reduce Scanned PDF Size Without Ruining Text
Scanned PDFs are heavy because each page is a full image. Use this guide to reduce size for email while keeping text readable.
Step 1: Choose a realistic target
Start with Gmail 25 MB or Outlook 20 MB presets. Scan-heavy documents often need smaller targets to fit reliably.
If your scan includes photos, expect a larger size and plan to split if needed.
Step 2: Use smart quality
Smart quality tries to keep the highest readable image quality that still meets your limit. It is ideal for scanned text and forms.
If the file still does not fit, the tool will split it instead of over-compressing.
Step 3: Avoid over-compression
Pushing quality too low can make text fuzzy. Use the balanced or high option and then rely on splitting when necessary.
A two-part PDF is often better than a single file with unreadable text.
Step 4: Download and review
Open the output to ensure text remains legible and pages are complete.
If needed, adjust the target and re-run the job for a better balance of size and clarity.
FAQ
Will OCR be affected?
Compression does not remove OCR text layers, but very aggressive image compression can reduce readability. Use balanced settings when OCR matters.
What DPI should I scan at?
150-200 DPI is usually enough for email and on-screen reading. Higher DPI increases size quickly.
Should I scan in color?
Grayscale is smaller and often clearer for text. Use color only when it adds necessary context.
Scan-friendly tips
Clean inputs compress better
Straighten pages and remove blank pages before uploading. Smaller inputs lead to smaller outputs.
If possible, crop to remove margins that add unnecessary pixels.
Split long scans
Long scan batches can be split into smaller parts for faster sending and easier review.
Use split-by-size if the scan must remain in order.
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