Upload Errors and File Size Limits for PDF Documents

Updated March 18, 2026 · 6 min read

An upload error is frustrating when the message is vague. Images are usually the reason a PDF becomes too large to email, so compressing them before inserting keeps the PDF small.

Recommended settings for PDF documents

SettingStarting point
FormatJPEG (WebP where accepted)
Widthabout 1600 px on the long edge
Quality78
File size200 KB or less

These are practical defaults. If the platform or form you are using publishes its own limits, follow those instead.

Upload Errors and File Size Limits

Most errors come from three causes: the file is too big, the dimensions are outside the allowed range, or the format is not accepted.

For PDF documents, convert to JPEG, resize to about 1600 pixels and compress below 200 KB. If the form lists its own limits, use those numbers instead.

Step by step with TheCompressJPEG

  1. Open the compress JPEG to 200 KB tool, or the main compressor for custom settings.
  2. Drop in your image. Nothing is uploaded; it is processed in your browser.
  3. Set the maximum width to 1600 and the target size to 200 KB.
  4. Press Compress, check the result and download it.
Ready to try it? Compress your JPEG to 200 KB now. It's free and private.

Quick tips

  • Always keep the original file and compress a copy.
  • Use JPEG for photos and PNG for logos and line art.
  • Name files descriptively with lowercase words and hyphens.
  • Check the result on a phone, where most people will see it.

FAQ

Can I compress images for e-learning courses without uploading them?

Yes. TheCompressJPEG runs entirely in your browser, so your images never leave your device.

Is WebP accepted for e-learning courses?

It depends on the platform. JPEG is the safest choice when you are not sure.

What size should an image be for e-learning courses?

A practical default is about 1600 pixels wide and 200 KB or less, unless the destination states its own limits.

Wrapping up

For PDF documents, the reliable recipe is simple: resize to around 1600 pixels, compress at quality 78 or to a 200 KB target, and check the result before you upload. Keep the original so you can always start again.

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