The Ultimate Guide to Custom Emoji for Slack, Discord & Teams
Jordan Park
April 5, 2026 · 2 min read
Custom emoji transform boring chat into something alive. They're inside jokes, team identity, and reaction culture — all in tiny animated squares. 
This guide covers everything.
Quick Stats
Teams with custom animated emoji see 2.3x more reactions per message and 40% higher engagement in channels.
Platform Requirements
| Platform | Max Size | Dimensions | Animated? | Limit |
|---|---|---|---|---|
| Slack | 128KB | 128×128 |  GIF | 500+ |
| Discord | 512KB | 128×128 | GIF | 50-250 |
| Teams | 1MB | 210×210 | GIF | 5,000 |
Step-by-Step Guides
💬 Slack
- Click the smiley face in chat
- Click Add Emoji
- Upload your GIF
- Name it (becomes :your-name:)
- Click Save
🎮 Discord
- Go to Server Settings
- Click Emoji sidebar
- Click Upload Emoji
- Select your GIF
- Name it and save
🏢 Teams
- Open any chat
- Click the emoji icon
- Click the + icon
- Upload from device
- Name and save
Pro Tips
Tip #1: Organize by prefix
Name emoji with prefixes: :react-thumbsup:, :status-done:. Groups them in the picker.
Tip #2: Optimize file sizes
Reduce frames (every other frame works), resize to exactly 128×128, reduce colors. Tools like ezgif.com can help.
Tip #3: The 80/20 rule
80% of usage comes from 20% of your collection. Focus on core 20-30 emoji first 
Build Your Collection
Reactions
thumbs up, clap, fire, eyes
Celebrations
party, confetti, trophy
Status
done, in-progress, blocked
Fun
parrots, memes, mascots
Get Started
Sources
- Animated vs Static Discord Emojis — MakeEmoji
- Slackmojis — Custom Slack Emojis
- Emoji.gg — Discord Emoji Directory
- GIF to Emoji Size Requirements — AnimGifMoji