How to Record and Transcribe Lectures on Mac (Offline)

To record a lecture on a Mac and get a transcript, open Rebrief for Mac before class, start a recording from the menu bar, and stop it when the lecture ends. Rebrief records your microphone and the audio your Mac plays, then transcribes it on your Mac. Check your course's recording rules first. An online lecture you only listen to needs a manual start, and the free plan covers recordings up to 15 minutes.

Once the models have downloaded, the transcript, notes and audio are all available offline. You can read the explanation you missed on a train or export it to listen elsewhere. You'll still need the slides for anything the lecturer only showed on screen.

Check whether you can record the lecture

Look first for an official recording or transcript. If your course already supplies one that covers what you need, start there. When you need your own copy, check that the course allows recording and keeping the audio for study, including other students' questions, and ask for permission where it is needed. Paying for a course does not by itself give you permission to copy it.

How to record a lecture on Mac

1. Set up while you have internet. Rebrief needs an Apple Silicon Mac with macOS 15 or later. Let the speech and notes models finish downloading, and allow both the microphone and Screen and System Audio Recording. The support page covers setup.
2. Record a short test. For an online lecture, play a minute of it and listen back to check the lecturer is audible. For a lecture in a room, test from where you usually sit; a laptop microphone at the back of a hall may not pick up the lecturer clearly.
3. Silence notifications. Rebrief records everything your Mac plays, including alert sounds.
4. Start recording from the menu bar before the explanation begins. Automatic recording only starts when an app uses your microphone and speakers at the same time, so a lecture you only listen to won't trigger it.
5. Note slide numbers and questions as you go, and let Rebrief keep the spoken explanation.
6. Keep the Mac awake and stop the recording when the lecture ends. Each recording stops before the Mac sleeps and has a hard limit of eight hours.

Free recordings stop cleanly at 15 minutes and are still transcribed in full. For a whole class, buy the one-time unlock before the lecture.

Getting a transcript you can study from

After you stop recording, Rebrief writes the transcript and then the notes, all on your Mac. Your microphone and the lecture audio are kept as separate tracks, and the language is detected for each side, so your own comments don't get mixed into the lecturer's words.

When you sit down to study, pick one question your own notes can't answer. Search the transcript for the term, then read the whole passage around it, including the setup and any condition that follows the definition. You can also ask a question in Ask, such as "What condition did the lecturer give for using this method?" Ask shows the transcript lines its answer came from, and selecting one opens the recording at that moment.

Check the words your understanding depends on. Compare technical terms with the course glossary or slides, and listen again to numbers and small words like "not", "only" and "unless". If the audio can't settle a point, write it down as a question for the lecturer rather than filling the gap yourself. The generated notes are good for seeing which topics were covered, but a short recap can skip a step in a derivation, so follow the full passage for the concept you are studying.

Then write a study note in your own words, with the condition or exception that mattered, the lecture title and a pointer to the passage. You can copy notes from Rebrief as Markdown or export the transcript into your usual study document.

Taking the lecture offline

Rebrief itself works offline, so you can open the recording and transcript in the app with no connection. Export them when you want to listen in another player or keep a copy with your course files.

1. Before you lose access to the course, play back the part you want and make sure the full explanation is there, including the question that led to it.
2. Use Export to save both audio tracks to a folder named after the course and the lecture topic.
3. Export the transcript as plain text or Markdown into the same folder. SRT and WebVTT are also available if you want timestamps.
4. Write down where the explanation starts in the audio.
5. Turn off Wi-Fi, close the course website, and open the audio once to check it plays. In QuickTime Player, choose File, then Open File, as described in Apple's playback guide.

For an online lecture, the lecturer is on the track with the audio your Mac played, and the other track is your microphone. In a room, the lecturer is on the microphone track. If you can only hear yourself, the system audio permission was probably missing. Grant it again in System Settings, Privacy and Security, Screen and System Audio Recording for future classes, and use a permitted replay or transcript to fill the gap for this one.

Bring the slides when the explanation needs them

Rebrief records audio, so "as you can see here" won't keep the graph, equation or demo the lecturer is pointing at. Save permitted slides or handouts in the same folder, and copy notation from the teaching material, including symbols and subscripts that were never spoken aloud. If you can't keep the visuals, write the explanation in your own words while you can still see them.

Common questions

Does Rebrief record the slides or video?

No. Rebrief records audio only, as two tracks: your microphone and what your Mac plays. Save permitted slides separately.

Can I record an in-person lecture with my MacBook?

Yes, through the Mac's microphone, with a manual start. Quality depends on how close you sit and how loud the room is, so test it first and check that the lecturer is clear.

Why didn't the recording start on its own?

Automatic recording needs an app to be using your microphone and speakers at the same time. Listening to a lecture uses only the speakers, so start the recording from the menu bar.

How long a lecture can I record?

Free recordings stop at 15 minutes. After the one-time purchase, a single recording can run up to eight hours.

A note on recording rules

Ask before you record a lecture, and follow your school's or course provider's rules on recording and keeping the audio. Rules and laws differ by place, and other students' voices may be on the recording too.

Next step

Record a permitted segment under 15 minutes on a topic you found hard, find the explanation in the transcript, and check it against the audio. For live sessions where you ask questions, see how to record a webinar or live class on Mac. For more on what works without a connection, read how to transcribe a meeting offline on Mac.