Start with a two-minute triage in the browser
Before opening a single settings pane, find out whether macOS itself is receiving sound. Open our mic test, click Allow when the browser asks, choose your microphone in the input device selector and speak. If the level meter and the real-time waveform follow your voice, the Mac has found the microphone, granted the browser access and is delivering audio to programs. In that case the operating system is not your problem: a particular app is listening to a different device, was never granted permission, or is fighting another program for the microphone, and our guide on a mic that works in the browser but not in Discord, Zoom or games is the right next stop. Nothing you say in the test is recorded or uploaded anywhere.
If the meter stays flat, or the selector does not list the microphone at all, the fault sits between the microphone and the macOS audio system, and that is what this guide works through. Note two things from the test before you move on. The device names in the selector tell you what macOS thinks is connected: 'MacBook Pro Microphone' or 'MacBook Air Microphone' is the built-in array, 'External Microphone' is something on the 3.5 mm jack, a product name is a USB device, and your AirPods or headset name means a Bluetooth input. And if the meter twitches faintly when you tap the microphone, signal is arriving and the input volume is simply near zero, which lets you skip straight to the Sound settings step.
The rest of the article proceeds from the most likely and least invasive cause to the least likely and most invasive one: privacy permissions, then the Sound input pane, then the device being missing entirely, then USB, Bluetooth and headphone-jack quirks, then macOS microphone modes, and finally the resets. Keep the test tab open while you go. The instant the meter starts moving you have found the broken layer and can stop, which is far more efficient than reading every section first and applying all of the fixes at once.
macOS privacy permissions: per-app toggles and the browser double-gate
macOS gates the microphone per application, and an app that has been denied receives pure silence rather than an error, which is why a working microphone can seem dead in one program. Open System Settings, then Privacy and Security, then Microphone. Every app that has ever asked to use the microphone appears here with a toggle. Turn on the one for the app that is failing, and then quit that app completely and relaunch it, because most programs only open the microphone at startup and a permission granted afterwards does not always take effect until the next launch.
The detail that trips people up is that an app only appears on this list after it has asked at least once. If the program you are troubleshooting is not listed, it has either never requested access or its request was dismissed before it could be recorded, so the fix is to make it ask again: open the app, start a call or a recording, and watch for the permission dialog. If the dialog never comes and the app never appears, the app may be using an older audio framework or a bundled helper process; check whether a companion app or an audio driver installed alongside it is the one listed instead. In stubborn cases, resetting the microphone permission database from Terminal with the tccutil command forces every app to ask again the next time it needs the microphone.
Browsers add a second gate. Chrome, Firefox, Edge and Safari must first be allowed under Privacy and Security, Microphone, and then each website must be allowed inside the browser as well. In Chrome and Edge, click the icon at the left of the address bar to see the site's microphone permission; in Safari, open Safari Settings, Websites, Microphone and set the site to Allow or Ask. If our test shows a permission error or an empty device list, this double-gate is almost always the reason, and it explains why the same site works in one browser and not another. The permission called Screen and System Audio Recording is a separate thing entirely, covering audio captured from other apps and the screen, and granting it does nothing for a microphone; likewise, a screen recorder that hears nothing needs microphone permission, not just screen permission.
Sound input settings, the orange dot, and the missing built-in microphone
Open System Settings, Sound, and select the Input tab. The list shows every input device macOS currently sees. Choose the one you are actually using, then look at the Input volume slider underneath. macOS remembers the input volume separately for each device, so a USB microphone can be at a healthy level while the built-in microphone you switched to today is sitting at zero. Raise the slider to somewhere around three quarters and speak. The Input level meter just below responds to sound in real time, and it is the most honest instrument on the Mac: it reflects what Core Audio is receiving before any app or browser touches it. If that meter moves, macOS is fine and the problem is in the app; if it stays dark with the slider up, macOS itself is not getting signal, and you continue down this guide.
While an app is using the microphone, macOS shows an orange dot in the menu bar next to the Control Center icon. Click Control Center and the name of the app that is recording appears at the top. This is useful in two directions. If the dot is missing while your app is supposedly listening, that app has not actually opened the microphone, which usually means a permission or device-selection issue inside the app. If the dot is present but a different app's name is shown, that program has the microphone and may be the reason yours is silent, so quit it. Some conferencing and dictation tools keep the microphone open in the background long after you think you have closed them.
If the built-in microphone is missing from the Input list entirely, check whether macOS knows about the hardware at a lower level. Open Audio MIDI Setup from the Utilities folder inside Applications. The sidebar lists every audio device Core Audio has loaded; a MacBook should show its microphone there even when the Sound pane is confused. If it is listed in Audio MIDI Setup but not in Sound, restarting the audio engine usually repairs the list: open Activity Monitor, search for coreaudiod, select it and click the stop button to force quit it. macOS restarts the process automatically within a second or two and rebuilds the device list. If the device is missing from Audio MIDI Setup as well, the operating system is not seeing the hardware, and the reset section at the end of this guide is the next step.
Two more things about the Input pane are worth knowing. First, when you plug a headset into the 3.5 mm jack, macOS switches the input to External Microphone automatically, but it does not always switch back when you unplug it, leaving the built-in microphone unselected; check the list after every plug and unplug. Second, changing the selection here is not the same as changing it in an app. Zoom, Discord, Teams and most other communication apps have their own input device menu that can point at something else and ignore this pane entirely, so once macOS is confirmed working, the app's own audio settings are where the remaining problem lives.
USB microphones, Bluetooth headsets and AirPods, and the headphone jack
USB microphones on a Mac rarely need drivers, so when one goes silent the usual causes are power and the port. A condenser microphone with a large diaphragm or built-in headphone amplifier can draw more current than a bus-powered hub provides, and the result is a device that appears in the list but produces nothing or drops out. Plug it directly into the Mac, or into a hub that has its own power supply. On Macs with USB-C only, some adapters and docks pass USB audio poorly; try a different adapter before blaming the microphone. Then open Audio MIDI Setup, select the microphone, and look at the Format menu. If the sample rate shown there does not match the one the app is asking for, some devices respond with silence or with audio that plays back at the wrong pitch; setting a common value such as 48,000 Hz here, and matching it inside the app if the app has such a setting, resolves it.
Bluetooth headsets and AirPods behave differently from wired gear because Bluetooth has two audio profiles. When only the headphones are in use, the Mac streams high-quality stereo. The moment an app opens the headset's microphone, the connection drops to the hands-free calling profile, which carries a narrower, lower-quality signal in both directions, and on some headsets there is a short gap while the switch happens that an app can interpret as no input. If your AirPods play music beautifully but their microphone is silent, look at Sound, Input: the AirPods must be selected as the input device there, and if they are missing from the list, disconnect and reconnect them from the Bluetooth menu. A useful alternative for calls at a desk is to select the AirPods for output but the MacBook's built-in microphone for input, which keeps the high-quality profile for what you hear and avoids the hands-free switch altogether.
The 3.5 mm jack on a MacBook is a combo jack that expects a four-contact TRRS plug wired to the CTIA standard, which is what nearly all modern headsets and Apple's own wired earphones use. Older headsets wired to the OMTP standard put the microphone and ground contacts in the opposite order and produce a silent or crackly microphone on a Mac; an OMTP-to-CTIA adapter fixes that. A microphone with a three-contact TRS plug, the kind that goes into a dedicated mic input on a desktop PC, has no contact for the jack to recognise as a microphone and will not work at all in the combo jack without a TRRS adapter or a USB interface. When a headset is plugged in correctly, Sound, Input shows External Microphone; if the entry never appears, the plug is not seated fully or the wiring standard is wrong, not the software.
Microphone modes, app-level device selection and audio processing
Recent macOS versions add microphone processing modes that are chosen from Control Center rather than from any app. While an app has the microphone open, click Control Center and look for the Mic Mode item at the top; it offers Standard, Voice Isolation and Wide Spectrum. Voice Isolation uses machine learning to remove everything that does not sound like a nearby voice, and Wide Spectrum does the opposite, passing the whole environment through. Voice Isolation can be too aggressive with soft speech, unusual microphones, or a voice picked up from across the room, sometimes cutting the level to almost nothing or making it pulse. If your microphone works but sounds oddly gated or muffled, set the mode back to Standard and compare in our test; the setting is remembered per app, so check it in each program where you noticed the problem.
The mode item only appears in Control Center while something is actively using the microphone, which confuses people looking for it in advance; open our test or start a call first, then open Control Center. The availability of these modes also depends on the Mac model and the app, so their absence is not a fault. Apps frequently layer their own processing on top: Zoom's background noise suppression, Discord's noise suppression and automatic gain, and Teams' noise suppression can all silence a quiet voice. For diagnosis, turn all of them off, confirm the raw microphone works, and then re-enable them one at a time.
Because apps keep their own input device selection, confirming the microphone in System Settings is only half the job. Zoom's audio settings, Discord's Voice and Video page, Teams' devices menu and OBS's audio input capture each have a microphone dropdown, and each can be set to a device that no longer exists or to a virtual audio device installed by some other tool. After you have used our test to prove which device actually hears you, open the app and choose that exact device by name. If you prefer the app to follow the system default, set it to the default option and remember that macOS may change the default whenever a headset is connected or disconnected. Our guide on mic problems that appear only inside a particular app walks through each of these programs in detail.
Resets, and the whole procedure as one ordered checklist
When the microphone is missing from Audio MIDI Setup or stops working across every app at once, the audio subsystem or the system controller may need a reset. On any Mac, the first move is a full restart, and on an Apple silicon Mac that is also the only move: the equivalent of the old SMC and NVRAM resets happens automatically at every boot, so shut the Mac down from the Apple menu, wait about thirty seconds, and start it again. On an Intel Mac, the traditional resets still apply. Reset the NVRAM by starting the Mac and holding Option, Command, P and R together for about twenty seconds. Reset the SMC on a MacBook with the T2 chip by shutting down, holding the right Shift, left Option and left Control keys for seven seconds, then adding the power button for another seven seconds, then releasing everything and turning the Mac on. Older Intel MacBooks use Shift, Control and Option on the left side together with the power button for ten seconds. If the microphone is still missing after these, starting in Safe Mode helps decide whether a third-party audio driver or virtual device is responsible, because Safe Mode loads without them.
Here is the whole method as one list, in the order that finds the cause fastest. Run our mic test; if the meter moves, stop and go to the in-app guide. Check the physical basics: headset mute switch, boom position, a direct port instead of a hub, and a fully seated plug. Open System Settings, Privacy and Security, Microphone, turn on the toggle for the app, and if the app is missing make it ask again; for a browser, also allow the site inside the browser. Open System Settings, Sound, Input, select the right device, raise the Input volume slider and watch the Input level meter. Look for the orange dot in the menu bar and quit any other app that is holding the microphone. Set Mic Mode to Standard in Control Center and turn off the app's own noise suppression.
If the device is missing, open Audio MIDI Setup to see whether Core Audio knows about it, force quit coreaudiod from Activity Monitor, and check the sample rate format for USB devices. For USB, plug in directly and try another cable or adapter. For Bluetooth, reconnect the headset, select it under Input, or use the built-in microphone for input instead. For the headphone jack, confirm the plug is TRRS wired to CTIA and that External Microphone appears in the list. Restart the Mac, and on Intel models reset NVRAM and the SMC; try Safe Mode if third-party audio software is installed. If a different microphone works on this Mac while this microphone is silent on every device you try, the microphone is faulty; if no microphone works on this Mac at all and even Audio MIDI Setup shows nothing, the hardware needs service. And once the meter moves again but the level is low or the sound is noisy, our guides on a microphone that is too quiet and on static, crackling and buzzing continue from here.