What you're actually recording when you capture computer audio

When you capture audio from your computer, you're recording the sound that comes out of your speakers — music from a browser tab, a video call, a game, a podcast app, whatever is playing through your system. The method you use depends on what you want to record and what operating system you're on. Some approaches record everything your computer outputs. Others let you pick a single app or window. Some require paid software; others use tools already built in.

The reason this matters: different situations need different tools. Recording a Zoom call uses a different path than recording background music from Spotify, which is different again from capturing audio while you're also speaking into a microphone. Understanding what you're trying to do first makes the technical part straightforward.

Key Takeaways

  • Windows 11 has a built-in tool called Voice Recorder that captures system audio, while Windows 10 requires third-party software or workarounds.
  • Mac users can use QuickTime Player to record system audio by changing the input source in the Sound settings, or use free tools like Audacity.
  • Audacity (free, works on Windows, Mac, and Linux) lets you record system audio, microphone audio, or both at the same time.
  • Some apps like Zoom, Discord, and OBS Studio have built-in recording features that capture both audio and video without needing separate software.
  • Browser-based tools like CapCut or Riverside.fm can record video calls and screen audio directly in your web browser.

Recording system audio on Windows 11

Windows 11 includes Voice Recorder, a built-in app that can capture system audio without installing anything. Open the Start menu, search for "Voice Recorder," and launch it. Click the microphone icon to start recording. By default, it captures your microphone input, but you can change this to record system audio instead.

To switch from microphone to system audio: open Settings, go to System > Sound, scroll down to Advanced, and look for App volume and device preferences. Find Voice Recorder in the list and change its input from your microphone to "Stereo Mix" or "What U Hear" (the name varies by sound card). Once that's set, Voice Recorder will capture whatever is playing through your speakers. The file saves as an M4A audio file in your Recordings folder.

Voice Recorder is simple but limited — it only records audio, not video, and it doesn't let you pick which app to record from. If you need more control, you'll need a third-party tool.

Recording system audio on Mac

QuickTime Player, which comes with every Mac, can record system audio. Open QuickTime Player, go to File > New Audio Recording. A small recording window appears with a red record button. Click the dropdown arrow next to the record button and select your Mac's internal speakers or audio output as the input source. Then click record.

The catch: QuickTime Player doesn't have a built-in way to select system audio as the input. You need to change your Mac's sound settings first. Go to System Settings > Sound, and under Output, note which device is selected. Then in QuickTime's recording window, that same device should appear in the input dropdown. If you don't see a system audio option, your Mac may not have Stereo Mix enabled, which means you'll need a free tool like Audacity instead.

Audacity works on Mac and is often simpler: download it from audacityteam.org, open it, go to Transport > Transport Options and enable "Software Playthrough," then select your system audio as the recording device. Click the red record button and play whatever you want to capture.

Using Audacity for flexible recording on any system

Audacity is free, open-source software that runs on Windows, Mac, and Linux. It lets you record system audio, microphone audio, or both at the same time, and gives you fine control over levels and quality. Download it from audacityteam.org (not from other sites, which may bundle unwanted software).

To record system audio in Audacity: open the app, look at the toolbar near the top. You'll see a dropdown that says "Microphone" or similar — click it and select your system audio device (called "Stereo Mix," "What U Hear," "Loopback," or "Mac Virtual Audio Device," depending on your system). If you don't see a system audio option, your computer may not have one enabled, and you'll need to enable Stereo Mix in your sound settings first.

Once the input is set, click the red record button. Audacity will capture everything playing through your speakers. When you're done, click the stop button (the yellow square), then go to File > Export and choose your format — MP3 or WAV are standard. Audacity also lets you trim, fade, or adjust volume before you export, which is useful if you recorded extra silence at the start or end.

Recording video calls and screen content

If you're recording a Zoom call, Teams meeting, or Google Meet, the app itself usually has a built-in record button. In Zoom, click the Record button during a call and choose "Record on this Computer." The recording saves to your Downloads folder as an MP4 file with both video and audio. Teams and Google Meet work the same way — look for a Record or Capture button in the call controls.

For screen recording with audio, OBS Studio (free, open-source) is the standard tool. Download it from obsproject.com. Create a new scene, add your audio source (system audio, microphone, or both), add a display capture source if you want to record your screen, then click Start Recording. OBS saves as an MP4 file and gives you precise control over what audio sources are included.

If you want something simpler and don't need to edit afterward, CapCut (free, web-based) lets you record your screen and system audio directly in your browser — no installation needed. Go to capcut.com, click Create, and select Screen Recording. It captures video and audio together and saves the file to your computer.

Enabling Stereo Mix or system audio capture on your device

Many recording tools need Stereo Mix (Windows) or a virtual audio device (Mac) to be enabled before they can capture system audio. If you open Audacity or Voice Recorder and don't see a system audio option in the input dropdown, this is usually why.

On Windows, right-click the speaker icon in the system tray, select "Open Sound settings," scroll down to Advanced, and click "App volume and device preferences." Look for Stereo Mix in the list. If it's not there, open Device Manager (search for it in the Start menu), find Sound, video and game controllers, right-click your audio device, and select Properties. Go to the Advanced tab and look for an option to enable Stereo Mix or "What U Hear." If you still don't see it, your audio driver may not support it — check your sound card manufacturer's website for updated drivers.

On Mac, system audio capture usually works through a virtual audio device. If QuickTime or Audacity don't show a system audio option, download and install Soundflower (free, from github.com/mattingalls/Soundflower) or BlackHole (free, from existential.audio). These create a virtual audio device that lets recording software capture system audio. After installing, set your Mac's output to the virtual device, then select it as the input in your recording app.

Choosing between recording formats and quality settings

Most recording tools let you choose a file format and quality level. MP3 is the most compatible — it plays on any device and takes up less space — but it compresses audio slightly. WAV is higher quality and better for editing, but files are much larger. M4A (used by Voice Recorder and iTunes) is a middle ground: good quality, smaller files, and compatible with most devices.

For sample rate, 44.1 kHz is standard for music and most purposes. 48 kHz is used in video production. Higher rates (96 kHz, 192 kHz) don't sound noticeably better for most listening and just make files bigger. Bit depth of 16-bit is standard; 24-bit is used in professional audio but unnecessary for most recording. In Audacity, go to Audio Setup and you'll see these options. For most people, the defaults (44.1 kHz, 16-bit, MP3) are fine.

Frequently Asked Questions

Can I record a Zoom call without the other people knowing?

Zoom notifies all participants when someone starts recording, and the recording indicator appears on screen. You cannot hide it. Some jurisdictions require all parties to consent to recording, so check your local laws before recording any conversation.

Why doesn't my computer have Stereo Mix or system audio capture?

Not all audio devices support it — some laptops and external sound cards don't have the driver support. If it's missing, try updating your audio drivers from your sound card or laptop manufacturer's website. If it's still not available, use a virtual audio device like Soundflower (Mac) or install a third-party audio loopback tool (Windows).

What's the difference between recording system audio and recording a microphone?

System audio is what plays through your speakers — music, videos, app sounds. Microphone audio is your voice or any sound in the room picked up by your mic. Most recording tools let you choose one or both. If you want to record yourself talking over a video or music, you need both inputs enabled at the same time.

Can I record audio from a specific app only, not everything playing?

OBS Studio and some advanced tools let you select individual apps as audio sources. Most simpler tools like Audacity or Voice Recorder capture all system audio at once. If you need to isolate one app, OBS is the most straightforward free option.

Do I need special permission to record audio from websites or apps?

Technically, recording copyrighted music or video without permission violates copyright law in most places, even if you're just recording it for personal use. Recording your own voice, a meeting you're part of, or content you created is fine. Check the terms of service for any app or website you're recording from — some explicitly prohibit it.