Free Slack Emoji Resizer
Free Slack emoji resizer for custom emoji (128x128 under 128KB). Resize Slack emoji instantly in your browser.
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Slack Emoji Size Requirements
Slack recommends custom emoji at 128x128 pixels for the best quality across all devices. While Slack will accept and resize larger images, starting with the correct dimensions ensures your emoji displays perfectly in messages, reactions, and status indicators. Our Slack emoji resizer automatically converts your image to exactly 128x128 pixels with optimal quality settings.
| Requirement | Specification |
|---|---|
| Dimensions | 128x128 pixels (recommended) |
| File Size | Must be under 128KB |
| Format | PNG, JPG, or GIF |
| Animation | GIFs supported (max 50 frames) |
Slack Emoji File Size Limit
Slack requires all custom emoji to be under 128KB in file size - stricter than Discord's 256KB limit. This can be challenging for detailed images or those with gradients. Our Slack emoji resizer automatically compresses your image using smart optimization to meet Slack's 128KB requirement while preserving visual clarity. The exact file size is displayed before you download.
How to Add Custom Emoji to Slack
After resizing your emoji with our Slack emoji resizer, go to your Slack workspace. Click your workspace name, then 'Tools & settings' > 'Customize workspace' > 'Emoji'. Click 'Add Custom Emoji', upload your resized image, and give it a unique name (lowercase letters, numbers, and underscores only). Your emoji will be instantly available to all workspace members.
Resize Slack Emoji Without Photoshop
You don't need expensive software like Photoshop to create Slack emoji. Our free Slack emoji resizer handles everything directly in your browser with no downloads or installations. Simply drag and drop your image, see the preview, and download the perfectly sized emoji instantly. Works on any device - desktop, laptop, tablet, or phone.
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Slack Emoji Resizer FAQ
Slack recommends 128x128 pixels for custom emoji. Our Slack emoji resizer converts your image to this exact size for optimal display across all devices and contexts - messages, reactions, and status indicators.
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