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44.1 kHz vs 48 kHz: which sample rate should you record at?

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

Record at the rate your source already runs at. macOS system audio on the author's Mac is captured at 48 kHz, video and streaming use 48 kHz, and CD and most music-only pipelines use 44.1 kHz. Both cover the full audible range (22.05 kHz and 24 kHz limits). The size difference is 9 percent: 16.5 versus 15.1 MB per minute at 24-bit.

What is the difference between 44.1 kHz and 48 kHz?

The sample rate is how many level measurements are stored per second. The highest frequency a rate can represent is half of it, the Nyquist limit: 22.05 kHz for 44.1 kHz and 24 kHz for 48 kHz (Wikipedia, Sampling). Human hearing tops out near 20 kHz, so both rates cover the whole audible band.

The two numbers exist for historical reasons rather than sonic ones. 44.1 kHz was chosen for the audio CD because early digital recorders stored audio on modified video equipment and the rate fit both PAL and NTSC frame rates while covering 20 kHz. 48 kHz became the professional video standard because it divides cleanly against 24, 25, 29.97 and 30 frames per second. Neither rate is "higher quality" in any way you can hear; the difference between them is compatibility and a 9 percent file-size gap. The choice of bit depth matters far more for recording, see 16-bit vs 24-bit.

Which sample rate should I choose for recording?

The single rule that avoids trouble: do not mix rates inside one project. Pick the rate of the destination and set every device to it before the take. Where that setting lives is covered in what sample rate does Mac system audio use.

Does 48 kHz make bigger files?

Yes, by 48 / 44.1 = 1.088, about 9 percent. Measured from 45 real stereo recordings on the author's Mac:

Over a 2-hour set that is 1.98 GB against 1.81 GB at 24-bit: 170 MB, less than the gap between bit depths (660 MB). MP3 does not care: 320 kbps is 2.4 MB per minute at either rate because the bitrate, not the sample rate, sets the size. Hours per GB and per-duration sizes for every combination are in how big is an audio recording per minute.

What happens if the sample rates do not match?

macOS resamples silently. If your interface runs at 44.1 kHz and the app or system output is at 48 kHz, Core Audio converts on the fly. Done once, at a good quality setting, this is inaudible. Done repeatedly across a workflow (record at 44.1, import into a 48 kHz video project, export, re-import) it stacks tiny errors and costs CPU. Apple's Audio MIDI Setup guide simply tells you to "Click the Format pop-up menu, then set the sample rate and bit depth" and to make sure they match your device (Apple, Set up audio devices).

Two failure modes to know. Changing a device's rate in Audio MIDI Setup while a recording is running can stall the input; a good recorder restarts capture, but the seconds in between are gone (see gaps and dropouts). And a DJ controller whose USB audio is fixed at 44.1 kHz will not follow a 48 kHz setting; the Mac converts instead. To convert a finished file, use afconvert -f WAVE -d LEI24@44100 in.wav out.wav (the @ suffix sets the target rate; -r 127 is the default, highest, converter quality).

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

Apple, Audio MIDI Setup User Guide

44.1 kHz vs 48 kHz for a stereo recording

Sample rateNyquist limit (kHz)MB per minute, 24-bitMB per minute, 16-bitGB per hour, 24-bitRate of macOS system audio on the author's MacTypical home
44.1 kHz22.0515.110.10.89noCD, music libraries, many DJ controllers
48 kHz2416.511.00.97yesvideo, streaming, ScreenCaptureKit system audio

Sizes measured on real files; the Nyquist limit is half the sample rate.

Where AirCheck fits

AirCheck ($39, macOS 14 or newer) does not ask you to pick a rate. It records system audio at the rate ScreenCaptureKit delivers (48 kHz on the author's Mac) and any Core Audio interface at the rate the device is set to, at 24-bit, then converts once at stop to WAV 16-bit, WAV 24-bit or MP3 320 kbps. So a Scarlett 8i6 set to 44.1 kHz gives a 44.1 kHz file and a Zoom capture gives 48 kHz, with no resampling inside the app.

When you do not need it: If you only need to change the rate of an existing file, afconvert with the @44100 or @48000 suffix is free and built in. If you need everything resampled live to one rate while mixing sources, Loopback or Audio Hijack handle that; AirCheck does not resample.

AirCheck records what your Mac plays, or any input, to one file. $39 once.

Buy AirCheck for $39

macOS 14 or newer. One-off payment. Fourteen-day refund, no questions asked.

Questions people ask

Is 48 kHz better than 44.1 kHz?

Not audibly. Both reproduce the full 20 kHz band (Nyquist limits 22.05 and 24 kHz). 48 kHz is the video standard and what macOS system audio uses; 44.1 kHz is the CD and music standard. Choose by where the file is going.

What sample rate should I use for recording a DJ set?

The rate your controller or interface runs at, usually 44.1 kHz for DJ hardware and libraries. The file is 15.1 MB per minute at 24-bit. Only choose 48 kHz if the set is going into a video edit.

Does sample rate affect MP3 size?

No. An MP3 at 320 kbps is 2.4 MB per minute whether the source was 44.1 or 48 kHz, because the bitrate fixes the size. Only PCM files (WAV, AIFF) grow with the sample rate, by about 9 percent from 44.1 to 48 kHz.

How do I change the sample rate on a Mac?

Open Audio MIDI Setup in Applications/Utilities, select the device, then use the Format pop-up menu to set the sample rate and bit depth. Do this before you start recording, not during a take.

Sources

Hannes Hennerbichler builds AirCheck and records his own DJ sets with it through a Focusrite Scarlett 8i6. Every step on this page was run on the macOS version stated above. Drafted with AI assistance, checked and edited by the author. About