Common Mistakes When Compressing Images for Online Forms

Updated May 17, 2026 · 6 min read

A few habits cause most of the blurry or oversized images we see. Web forms often reject attachments above a set size, and the error message is not always clear about why.

Recommended settings for online forms

SettingStarting point
FormatJPEG (WebP where accepted)
Widthabout 1000 px on the long edge
Quality70
File size100 KB or less

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

Common Mistakes When Compressing Images

Compressing the same JPEG again and again stacks artefacts each time, so always work from the original. Setting quality very low on a huge image gives a small file that looks muddy; resizing first is better.

Another mistake is ignoring orientation. Phones store rotation in metadata, and some tools drop it, leaving sideways photos. Our tool applies the correct orientation before compressing, so what you see is what you get for online forms.

Step by step with TheCompressJPEG

  1. Open the compress JPEG to 100 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 1000 and the target size to 100 KB.
  4. Press Compress, check the result and download it.
Ready to try it? Compress your JPEG to 100 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

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.

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.

Wrapping up

For online forms, the reliable recipe is simple: resize to around 1000 pixels, compress at quality 70 or to a 100 KB target, and check the result before you upload. Keep the original so you can always start again.

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