What Is File Size?
Electronic file size refers to how much space a file takes up on a computer or online storage. It is not just based on word or page count—a short document with high-quality images or an improperly scanned file can be much "larger" than a long, text-heavy one.
File sizes are typically measured in:
- Kilobytes (KB) – Very small files (e.g., a short Word document or a small image).
- Megabytes (MB) – Larger files (e.g., a scanned document, presentation, or high-resolution image).
- Gigabytes (GB) and beyond – Very large files (e.g., videos, large databases).
Just 1MB can hold about 500 pages of text, so when a document is unusually large, it is often due to the way it was saved or scanned, rather than the number of pages.
If you’re unsure whether a file is too large, right-click it and check "Properties" (Windows) or "Get Info" (Mac) to see the size.
Why File Size Matters
Large files can cause unexpected problems when emailing or uploading them:
- Emails may fail to send if the file is too large. Many email providers limit attachments to 20-25MB, sometimes even smaller.
- Storage fills up faster. Large files take up more space on your device, and cloud storage services (like Google Drive or OneDrive) have storage limits.
- Uploads can be slow or fail. Many online forms—including OCR’s—have a file size limit to prevent slow or failed uploads.
- It affects the recipient. If you send a large file to someone, it takes up their email storage or data limit, especially if they are on a mobile device or slow internet connection.
As a general rule, try to keep everyday files under 1MB whenever possible. For text-heavy documents (without large images), this is easily achievable with the right settings.
How to Reduce File Size
Adjust Scanner Settings for Future Files
Many scanners default to high-resolution settings that create unnecessarily large files—even for simple documents. If you’re scanning a text-based document (such as a contract, letter, or form), use these settings. If you’re unsure how to adjust these, look for a “Settings” or “Options” button in your scanning software or on the scanner’s screen.
- Resolution: 200 DPI (dots per inch) is usually enough for clear text. 300 DPI is fine if needed, but avoid 600+ DPI unless absolutely necessary.
- Color Mode: Use Black & White (or Grayscale) for text-only documents. Color scanning creates much larger files.
- File Format: If possible, save as a PDF instead of an image file (like JPEG or PNG), which takes up more space.
Compress Existing Files
If you already scanned a large file, you can shrink the file size without losing readability.
- For PDFs: Use an online compressor for non-confidential documents, like Adobe's PDF Compressor. These tools can reduce file size in seconds without affecting text clarity.
- For Images: If your document contains large images, you can reduce the file size using tools like TinyPNG for non-confidential documents, or by saving the image as JPEG instead of PNG or BMP.
Save Text Documents Efficiently
If you are working with a Word document or similar file, you can prevent unnecessary bloat by:
- Avoiding large embedded images (resize them before adding them).
- Using “Save As” and selecting a compressed format, like PDF (Reduced Size) in Microsoft Word.
- Not copying and pasting from websites—this can add hidden formatting that increases file size.
What If I Need to Send a Large File?
Sometimes, large files are unavoidable. If you must send a file over 10MB, consider these options:
- Use a cloud storage link – Upload the file to Google Drive, Dropbox, or OneDrive and share the link instead of attaching the file.
- Zip the file – Right-click the file on your computer and select “Send to Compressed (Zipped) Folder” to create a smaller version.
- Break it into multiple files – If possible, split the file into smaller sections and send them separately.
Final Thoughts
Understanding file sizes is increasingly important in digital work. Keeping files small and manageable makes it easier to send, store, and upload them without issues.
If your scanned file is too large for an upload, email, or storage:
- Check your scanner settings first for future scans.
- Compress the file using an online tool if it’s already scanned.
- Be mindful of file sizes when sending to others.