Microphone not working in Slack

When your mic works elsewhere but not in Slack, the culprit is usually the input device chosen inside Slack or a missing permission. Confirm the mic works first, then fix Slack.

Test your microphone right now — it takes one click. Run the microphone test →

Step-by-step fix

  1. First, confirm the mic itself works: run the CheckMyMic microphone test.
  2. In Slack, open Preferences → Audio & video → Microphone and select the correct input device.
  3. Check the input level and make sure you're not muted inside Slack.
  4. Grant Slack microphone permission at the operating-system level.
  5. Restart Slack and rejoin your call.

Frequently asked questions

My mic works in the browser test but not in Slack — why?

That points to Slack's own device settings. Open Preferences → Audio & video → Microphone and pick the same microphone that worked in the test.

Does Slack need separate mic permission?

Yes — even if your browser or system has access, Slack may need its own grant. Allow it in your OS privacy settings, then restart Slack.

Fixed it? Confirm with a quick test. Run the test →

Related guides

← All troubleshooting guides · Interview-ready check →