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What sample rate does Mac system audio use?

Tested on macOS 26.4.1 (Tahoe), Apple M3 Max, 3 Sept 2026. Updated 2026-09-03.

On the author's Mac running macOS 26.4.1, system audio captured through Apple's ScreenCaptureKit arrives at 48 kHz, and every real system-audio file in a 45-recording sample is 48 kHz. The rate of what you hear is a per-device setting in Audio MIDI Setup (Applications/Utilities), changed with the Format pop-up menu. Interfaces record at their own rate, 44.1 or 48 kHz in real files.

What sample rate is macOS system audio recorded at?

48 kHz. That is the measured rate of every system-audio take in the author's library of 45 recordings on an Apple M3 Max Mac running macOS 26.4.1, where system audio is captured through ScreenCaptureKit (the API macOS 13 and later provide for recording what the Mac plays; see what is ScreenCaptureKit audio capture). The files are 24-bit and, at 48 kHz stereo, weigh 16.5 MB per minute, 0.97 GB per hour.

Two caveats keep this honest. First, it is one Mac and one output configuration, the built-in output; Apple does not document a fixed rate for ScreenCaptureKit audio, so treat 48 kHz as the observed value, not a guarantee. Second, the apps you record do their own thing: a 44.1 kHz Spotify stream or a 44.1 kHz WAV in a browser is resampled by macOS to the output device's rate before it reaches the mixer that ScreenCaptureKit taps. Recording that at 48 kHz stores a resampled copy, which is normal and inaudible at Core Audio's default converter quality.

How do I check or change the output sample rate on a Mac?

1. Open Audio MIDI Setup from Applications/Utilities (or search it in Spotlight).
2. Select the output device in the left column, for example MacBook Pro Speakers, or your interface.
3. Apple's guide: "Click the Format pop-up menu, then set the sample rate and bit depth", and "make sure they match the appropriate settings for your audio device" (Apple, Set up audio devices).
4. Do this before you start a recording. Changing the rate while a take is running restarts the audio stream, and the seconds around the change are lost; see gaps and dropouts.

The Format pop-up is per device. Built-in speakers, a USB interface, AirPods and a display's HDMI audio each keep their own rate, and macOS switches when you switch output. Apps that own a device exclusively, such as DAWs and DJ software, can change the rate underneath you; if your system-audio files come out at an unexpected rate, look for one of those running. The wider Audio MIDI Setup tour is in what is Audio MIDI Setup on a Mac.

Should I record system audio at 44.1 or 48 kHz?

Record at the rate the capture delivers, 48 kHz here, and convert afterwards only if a destination demands 44.1 kHz. Reasons:

• Forcing 44.1 kHz on a 48 kHz stream means a second resample, on top of the one macOS already did for the player. One conversion is inaudible; the fewer, the better.
• 48 kHz is what video editors and streaming platforms expect, so a screen capture's audio drops into Final Cut or Resolve without conversion.
• The size cost is 9 percent: 16.5 MB per minute versus 15.1 MB at 24-bit, 11.0 versus 10.1 at 16-bit, from the measured table in how big is an audio recording per minute.

If a file must be 44.1 kHz, for a CD project or a DJ library that is all 44.1, convert once with Apple's built-in tool: afconvert -f WAVE -d LEI24@44100 in.wav out.wav. The default sample-rate converter quality is already the maximum (-r 127). The general decision between the two rates is in 44.1 kHz vs 48 kHz.

Does the rate change with AirPods or an audio interface?

For a Core Audio input (an interface, a USB mic, a DJ controller's USB return) the recorder gets the device's own rate, not the system output's. In the author's real files from interfaces both 44.1 kHz and 48 kHz appear, because the Scarlett 8i6 and the controller were set differently on different days. Those files weigh 15.1 or 16.5 MB per minute at 24-bit accordingly. The rule is simple: set the interface to the rate your DJ or DAW software uses, then record; the file matches. For a step-by-step DJ setup see how to record a DJ mix with an audio interface.

For system audio, the output device matters less than people fear: ScreenCaptureKit taps the mixed system audio, and on this Mac that was 48 kHz with the built-in output. With AirPods as output, capture still works, but the moment an app opens the AirPods microphone, Bluetooth switches to its headset profile and the sound you hear degrades; that trap and how to avoid it are in does Mac system audio recording work with headphones or AirPods. The rate of the AirPods themselves was not measured for this page and is not claimed.

Click the Format pop-up menu, then set the sample rate and bit depth.

Apple, Audio MIDI Setup User Guide

Sample rate by source, as seen in real recordings on the author's Mac

Measured on macOS 26.4.1, Apple M3 Max, Sept 2026. Rates on other Macs or outputs may differ; check Audio MIDI Setup.

Where AirCheck fits

AirCheck ($39, macOS 14 or newer) records system audio at the rate ScreenCaptureKit hands it, 48 kHz here, and Core Audio inputs at the device's rate, always at 24-bit, with no resampling of its own. The Library shows each take's duration and size so a mismatch is visible at once (a 48 kHz hour is 0.97 GB, a 44.1 kHz hour 0.89 GB). The export you chose, WAV 16-bit, WAV 24-bit or MP3 320 kbps, is applied once at stop.

When you do not need it: To see or change the rate you need nothing but Audio MIDI Setup, which is free and already installed. If you need live resampling of several sources to one rate, Loopback or Audio Hijack do that and AirCheck does not.

Questions people ask

Is Mac audio 44.1 or 48 kHz?

It depends on the selected output device's Format setting in Audio MIDI Setup. On the author's Mac the built-in output and the ScreenCaptureKit system-audio capture were 48 kHz in every real file. Interfaces run at their own rate, commonly 44.1 or 48 kHz.

How do I change the sample rate on a Mac?

Open Audio MIDI Setup in Applications/Utilities, select the device, and use the Format pop-up menu to set the sample rate and bit depth. Set it before recording; changing it mid-take causes a gap.

Does the sample rate of system audio affect quality?

Not audibly at 44.1 or 48 kHz; both cover the full hearing range. What matters is avoiding repeated conversions. Record at the rate the capture delivers and convert once at the end if a destination needs a different one.

What sample rate do AirPods use for recording?

This page does not claim a figure; it was not measured. What is documented is the behaviour: when an app opens the AirPods microphone, Bluetooth switches to its headset profile and playback quality drops, so use the built-in or a wired mic when you also need good playback.

Sources

• Apple: Set up audio devices in Audio MIDI Setup
• ss64: afconvert man page (data_format@sample_rate, -r src quality)
• AirCheck: capture format, measured rates and sizes from 45 recordings (first-party)

Related guides

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• How big is an audio recording per minute on a Mac?
• Why is there a gap or dropout in my Mac recording?
• What is Audio MIDI Setup on a Mac?
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