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How long can you record audio on a Mac?

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

You can record audio on a Mac for as long as your disk holds out; macOS imposes no time limit and neither does AirCheck. Measured on 45 real recordings, 24-bit 48 kHz stereo uses 0.97 GB per hour, 16-bit 48 kHz uses 0.64 GB, and MP3 320 kbps uses 0.14 GB. The author's longest continuous take is 7,550 seconds (2 h 5 min) at 2.07 GB. The practical ceilings are disk space, the 4 GiB WAV limit, and sleep.

Is there a time limit for recording audio on a Mac?

Not in the operating system. Apple's Voice Memos guide describes Record, Pause, Resume and Done and mentions no maximum length; QuickTime's recording guides say nothing about a limit either. Recorders that stop early do so because of their file format or their own design, not because macOS ends the take.

The format limit that matters is WAV. Wikipedia's summary of the specification: "The WAV format is limited to files that are less than 4 GiB, because of its use of a 32-bit unsigned integer to record the file size in the header." At the measured 0.97 GB per hour for 24-bit 48 kHz stereo, 4 GiB arrives after roughly 4 hours 25 minutes. At 16-bit 48 kHz (0.64 GB per hour) it is about 6 hours 40 minutes. MP3 has no such ceiling in practice.

AirCheck has no length limit in the app. The longest continuous take in the author's own library is 7,550 s, 2 h 5 min, at 24-bit 48 kHz, weighing 2.07 GB. That is a single DJ set through a Scarlett 8i6, described in recording a DJ set on a Mac. Longer takes are only a disk question.

How many hours of audio fit in 1 GB?

Derived from the measured rates in the table below (45 recordings, 3 Sept 2026):

So a 256 GB Mac with 50 GB free holds roughly 50 hours of 24-bit 48 kHz, or about 350 hours of MP3 320. Uncompressed size scales with bit depth times sample rate times channels, which is why 16-bit is exactly two thirds of 24-bit at the same rate. The trade-offs are in 16-bit vs 24-bit and how big is a recording per minute.

How do you plan disk space for a long recording?

  1. Check free space: Apple menu > About This Mac > Storage, or df -h / in Terminal.
  2. Multiply the planned hours by the GB-per-hour figure for your format, then double it. The doubling is a judgement, not a measurement: it covers a take that runs long and the temporary space some recorders need during export.
  3. Choose the format to fit. A 6-hour livestream at 24-bit 48 kHz is about 5.8 GB and would also cross the 4 GiB WAV limit, so choose MP3 320 (about 0.84 GB) or plan to split the take.
  4. Record to the internal SSD, not to a USB stick or a network share, and move the file afterwards.

AirCheck-specific detail: the app captures to a 24-bit AIFF master and converts to your chosen export (WAV 16-bit, WAV 24-bit or MP3 320) when the take stops, so at the moment of export both the master and the export exist briefly. Budget for the AIFF size (16.5 MB per minute at 48 kHz) plus the export. Files land in ~/Music/AirCheck named with the date and time, and the Library shows duration and size per take.

What stops a long recording early?

Four things, in the order they usually turn up:

  1. Sleep. A closed lid or an idle display timer can suspend the recorder. Keep the Mac awake for the duration; see recording stops when the display sleeps.
  2. Disk full. The write fails and the file is truncated at whatever was flushed. The planning step above prevents it.
  3. Device loss. A USB interface that resets or a hub that re-enumerates after a power blip. Core Audio gives the device a new ID when it returns. AirCheck re-resolves it by name and its watchdog, which checks every 2 seconds, restarts capture into the same file after 5 seconds without buffers, retrying indefinitely. Command-line tools and simple recorders end the take instead.
  4. Format ceiling. The 4 GiB WAV limit, already covered. AirCheck's export writes WAV only after the take, so a take longer than the limit should be exported as MP3 or split.

None of these is a macOS time limit. Given power, an awake display and enough disk, an overnight take is routine.

Recording length by format, measured on 45 real recordings (Sept 2026)

FormatMB per minuteGB per hourHours per 10 GBSize of a 2 h 5 min takeHours to reach 4 GiB (WAV)
MP3 320 kbps2.40.14710.30 GBn/a
16-bit stereo 44.1 kHz WAV10.10.59171.26 GBabout 7.3
16-bit stereo 48 kHz WAV11.00.6415.61.38 GBabout 6.7
24-bit stereo 44.1 kHz WAV/AIFF15.10.8911.21.89 GBabout 4.8
24-bit stereo 48 kHz WAV/AIFF16.50.9710.32.07 GB (measured)about 4.4

MB per minute and GB per hour are measured; the remaining columns are arithmetic from those figures. The 2.07 GB take is the author's real longest recording.

Where AirCheck fits

AirCheck is built for long unattended takes: no length limit, a 24-bit AIFF master at 48 kHz, a watchdog that checks every 2 seconds and restarts a stalled capture into the same file, device re-resolution by name after a reconnect, and a Library that shows duration and size so you can see how much disk each take costs. Export to WAV 16-bit, WAV 24-bit or MP3 320 when the take ends. $39 once, macOS 14 or newer.

When you do not need it: For a short voice note, Voice Memos is free and its compressed files are tiny. AirCheck has no scheduling and no automatic file splitting; scheduled start and stop is a feature Audio Hijack lists on its product page.

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

How long can you record a voice memo on Mac?

Apple's Voice Memos guide states no maximum length. The recording continues until you click Done or the disk fills. Voice Memos files are compressed, so they are far smaller than the WAV figures on this page.

How long can QuickTime record audio on a Mac?

Apple documents no time limit for QuickTime audio or screen recordings. The practical limits are free disk space and the Mac staying awake; the screen recorder also produces large video files.

How much space does 1 hour of audio take on a Mac?

Measured: 0.97 GB at 24-bit 48 kHz stereo, 0.64 GB at 16-bit 48 kHz, 0.14 GB as MP3 320 kbps. A one-hour take fits comfortably on any Mac in any of these formats.

Can I record for 8 hours on a Mac?

Yes, given about 8 GB free for 24-bit 48 kHz, an awake display and power. Export to MP3 320 or split the take, because a single WAV cannot exceed 4 GiB, which 24-bit 48 kHz reaches after roughly 4 hours 25 minutes.

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