Why can't I record system audio on macOS Safari / Firefox?

Browser support for capturing system/tab audio via getDisplayMedia is patchy. Chrome and Edge support it for browser tabs (you'll see a "Share tab audio" checkbox in the picker). Firefox doesn't support it. Safari doesn't expose it. For full-system audio capture on Safari/Firefox, use OBS or a desktop tool.

Why is the output WebM, not MP4?

Browsers' MediaRecorder API outputs WebM (with VP8/VP9 video and Opus audio). MP4/H.264 recording is not consistently supported across browsers. WebM plays in Slack, Discord, Notion, GitHub, every modern web context — convert to MP4 with ffmpeg if a destination demands it.

Is my recording uploaded anywhere?

No. The screen capture stream goes straight from the OS to the browser to a MediaRecorder — never to a server. Open DevTools → Network and you'll see zero requests during recording. The only network activity comes after you click Download (and that's just the file save dialog).

What's the longest I can record?

Soft limit is your browser's memory. A 1080p screen recording uses roughly 300 MB of memory per 10 minutes. Most laptops can handle 30–60 minute sessions before getting sluggish. For longer, use a desktop tool that streams to disk continuously.

Can I record multiple monitors?

The browser picker only lets you record one source at a time — full screen, single window, or single tab. To capture multiple displays in one recording, use a desktop recorder like OBS that can composite them.

Why does the recording include the browser's "You're sharing this tab" notification bar?

If you record the same tab you're sharing from, yes — the bar is part of the captured content. Move to a different window/tab before recording, or record Entire Screen and crop the bar out in post.

Audio, Video & Voice · Free tool

Screen Recorder

Record your screen, a window, or a browser tab instantly online with no install. Download your recording as WebM free and save it in seconds.

Updated June 2026

Also record microphone (voiceover)

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Choose a screen, window, or browser tab in the permission prompt.

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What it does

Record your screen — full display, a single window, or just a browser tab — directly from the browser. Optionally include your microphone for narration, or your system audio (where the OS allows it) for capturing sound from a video call, tutorial, or app you're recording. No installs, no Loom watermark, no upload, no time limit, no signup.

Use cases run wide: quick bug-repro recordings for engineering tickets, tutorial loops for documentation, walkthrough demos for product calls, before/after clips when reviewing UX, and screen-share captures from a video meeting where the platform doesn't let you save the recording. The output is a WebM file (VP8/VP9 video + Opus audio if you included a mic).

Built on the browser's navigator.mediaDevices.getDisplayMedia()API. The OS controls which screen/window you pick (you'll see the standard system picker), and the browser is the only thing that ever sees your recording — there's no remote endpoint involved. File stays in browser memory until you click Download.

Embed this tool on your siteShow snippet

Paste this snippet into any page. Loads on-demand (lazy), no tracking scripts, and sized to most dashboards. Replace the height to fit your layout.

<iframe src="https://freetoolarena.com/embed/screen-recorder" width="100%" height="720" frameborder="0" loading="lazy" title="Screen Recorder" style="border:1px solid #e2e8f0;border-radius:12px;max-width:720px;"></iframe>

Embed docs →

How to use it

Decide whether to include audio: toggle Microphone (your voice) and System audio (sounds from the recorded window). System audio works in Chrome/Edge for browser tabs only — Firefox/Safari don't support it as of 2026.
Click Start Recording. The browser's screen-picker dialog opens — choose Entire Screen, a Window, or a Browser Tab.
Once recording starts, the picker closes and a small "Sharing this tab/screen" indicator appears (this is the browser's, not ours).
Click Stop when done. The clip appears with a play button — review before saving.
Click Download to save a WebM file. Drag straight into Slack/Notion/Confluence/GitHub — they all render it inline.

When to use this tool

Recording bug repros to attach to a Linear / Jira ticket.
Making short tutorial clips for a product onboarding doc or wiki.
Capturing a demo/walkthrough for an async team update.
Recording a workflow you want to remember (your own how-to library).

When not to use it

Long recordings (>30 minutes) — browser memory is a soft cap, and the WebM file balloons. Use OBS or a desktop recorder for extended sessions.
Multi-cam / picture-in-picture (your screen + your face) — that's a feature of OBS/Loom/Riverside, not the browser API.
Editing the clip afterward (cut, trim, add captions) — output is single-take. Use a video editor for post-production.
Capturing system audio on Firefox/Safari — those browsers don't expose it through getDisplayMedia.

Common use cases

Pre-decision sanity-check on inputs and outputs
Educational use — demonstrating the underlying concept
Onboarding a colleague who needs the same calculation/conversion
Verifying a number or output before passing it on

Frequently asked questions

Why can't I record system audio on macOS Safari / Firefox?: Browser support for capturing system/tab audio via getDisplayMedia is patchy. Chrome and Edge support it for browser tabs (you'll see a "Share tab audio" checkbox in the picker). Firefox doesn't support it. Safari doesn't expose it. For full-system audio capture on Safari/Firefox, use OBS or a desktop tool.
Why is the output WebM, not MP4?: Browsers' MediaRecorder API outputs WebM (with VP8/VP9 video and Opus audio). MP4/H.264 recording is not consistently supported across browsers. WebM plays in Slack, Discord, Notion, GitHub, every modern web context — convert to MP4 with ffmpeg if a destination demands it.
Is my recording uploaded anywhere?: No. The screen capture stream goes straight from the OS to the browser to a MediaRecorder — never to a server. Open DevTools → Network and you'll see zero requests during recording. The only network activity comes after you click Download (and that's just the file save dialog).
What's the longest I can record?: Soft limit is your browser's memory. A 1080p screen recording uses roughly 300 MB of memory per 10 minutes. Most laptops can handle 30–60 minute sessions before getting sluggish. For longer, use a desktop tool that streams to disk continuously.
Can I record multiple monitors?: The browser picker only lets you record one source at a time — full screen, single window, or single tab. To capture multiple displays in one recording, use a desktop recorder like OBS that can composite them.
Why does the recording include the browser's "You're sharing this tab" notification bar?: If you record the same tab you're sharing from, yes — the bar is part of the captured content. Move to a different window/tab before recording, or record Entire Screen and crop the bar out in post.

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