How to Compress Images for Slack Messages on Android
Android phones can compress images right in the browser. Shared images live in workspace storage and get re-downloaded by every viewer, so smaller is kinder to everyone.
Recommended settings for Slack messages
| Setting | Starting point |
|---|---|
| Format | JPEG (WebP where accepted) |
| Width | about 1600 px on the long edge |
| Quality | 78 |
| File size | 500 KB or less |
These are practical defaults. If the platform or form you are using publishes its own limits, follow those instead.
How to Compress Images
Open Chrome, load TheCompressJPEG, and tap the file picker to choose images from your gallery or file manager.
Pick a maximum width of 1600 pixels or a target of 500 KB, then tap Compress and Download. The files land in your Downloads folder, ready for Slack messages.
Step by step with TheCompressJPEG
- Open the compress JPEG to 500 KB tool, or the main compressor for custom settings.
- Drop in your image. Nothing is uploaded; it is processed in your browser.
- Set the maximum width to 1600 and the target size to 500 KB.
- Press Compress, check the result and download it.
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 Slack messages, the reliable recipe is simple: resize to around 1600 pixels, compress at quality 78 or to a 500 KB target, and check the result before you upload. Keep the original so you can always start again.
Related guides
- How to Compress Images for Slack Messages on Windows
On Windows, a browser-based compressor avoids installing extra software.
- How to Compress Images for Slack Messages on Mac
Mac users can compress JPEGs without opening Preview or Photoshop.
- How to Compress Images for Slack Messages Without Losing Quality
Strictly speaking, JPEG compression always discards something, but you can make the loss invisible.
- Batch Compressing Photos for Slack Messages
When you have dozens of images, consistency matters as much as size.
- How to Compress Images for Landing Pages on Windows
On Windows, a browser-based compressor avoids installing extra software.
- How to Compress Images for Restaurant Menus Online Without Losing Quality
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