Slack Emoji Reactions
An emoji reaction is a small image you attach to any message to respond without typing a word. Reactions reduce unnecessary replies, show team sentiment instantly, and keep channels from filling with "thanks!", "noted", or "+1" messages.
How Reactions Work
CHANNEL WITHOUT REACTIONS CHANNEL WITH REACTIONS
────────────────────────── ──────────────────────────────
Alice: "Design is ready." Alice: "Design is ready."
Bob: "Thanks!" 👍 3 ✅ 2 🎉 1
Carol: "Got it!" (Bob, Carol, Dave all reacted)
Dave: "👍"
→ Same information, less clutter
4 messages to convey agreement → 1 message + 3 reactions
Reactions sit directly below the message. Each emoji shows a counter for how many people reacted with it. Hover over the counter to see exactly who reacted.
How to Add a Reaction
Method 1: Hover and Click the Emoji Icon
- Hover your mouse over any message.
- A small toolbar appears to the right of the message.
- Click the smiley face icon (😊).
- The emoji picker opens — search or browse for an emoji.
- Click an emoji to add your reaction.
Method 2: Click an Existing Reaction
If someone already reacted with 👍 and you agree, click the existing 👍 reaction. Your reaction adds to the same emoji, and the counter increases by one. This is faster than opening the full emoji picker.
Method 3: Type a Colon in the Message Box
You can also react from within the message input area. Type : followed by the emoji name (e.g., :thumbsup:) and Slack autocompletes. This method works only when composing new messages, not for reacting to existing ones.
Mobile: Long-Press to React
On the mobile app, long-press (tap and hold) any message. A quick-reaction bar appears with six frequently used emojis. Tap one to react, or tap the "+" to open the full emoji picker.
Removing a Reaction
Click your own reaction to toggle it off. The counter decreases. If you were the only person who used that emoji, it disappears from the message entirely.
Common Reaction Conventions
Many teams adopt informal conventions for what specific reactions mean. Setting these expectations early helps the whole team communicate without words.
COMMON REACTION MEANINGS 👍 = Acknowledged / Agreed / Sounds good ✅ = Task is done / Confirmed complete 👀 = I am looking at it / On it 🎉 = Great news! / Congrats! ❓ = I have a question about this 🔥 = Impressive / Exciting ⏰ = This is time-sensitive ❌ = Declined / Not approved 💯 = Fully agree / Perfect
Some teams pin these definitions in their #general channel so everyone knows the code.
Custom Emoji
Workspace admins and members can upload custom emoji. Custom emojis are created from images and appear alongside standard emojis in the picker. Many teams create emojis that match their brand, inside jokes, or company culture — such as the company logo, a mascot, or a team-specific icon.
How to Add a Custom Emoji
- Click your workspace name at the top of the sidebar.
- Select "Settings & administration" → "Customize [workspace name]".
- Click the Emoji tab.
- Click "Add Custom Emoji".
- Upload an image (PNG or GIF, ideally 128×128 px).
- Give the emoji a name (this becomes its colon code:
:emoji-name:). - Click Save.
Custom emojis are available to everyone in the workspace immediately after saving.
Reactions as a Workflow Tool
Savvy teams use reactions as lightweight status indicators to track tasks without a separate tool.
TASK TRACKING WITH REACTIONS Alice posts: "Please review the Q3 report 👆" Bob reacts with 👀 → "I'm reviewing it" Bob then reacts with ✅ → "Review done" Carol reacts with ✅ → "Also reviewed" Alice sees two ✅ → knows two people reviewed it ✓
Key Takeaways
- Emoji reactions replace "thanks", "noted", and "+1" messages that clutter channels.
- Hover over a message and click the smiley icon to open the emoji picker.
- Click an existing reaction to add your own to the same emoji quickly.
- On mobile, long-press a message to access quick reactions.
- Teams create custom emoji to express team-specific ideas, culture, and status.