Is the recording uploaded anywhere?
No. The mic stream goes through MediaRecorder in your browser tab, the resulting blob lives in tab memory, and the MP3 export runs in-browser with FFmpeg/WebAssembly. Nothing leaves your device unless you upload the downloaded file yourself. Open the browser network tab while recording and you will see zero requests go out.
Why does my MP3 take a few seconds longer than the WebM?
Because MP3 export re-encodes the audio. WebM/Opus is what the browser already produced, so it is instant. MP3 needs to load FFmpeg (~25 MB the first time, cached after) and re-encode through libmp3lame. After the first run FFmpeg stays warm and subsequent exports are quick.
What is the bitrate and quality?
Native: Opus at whatever the browser picks (typically 64–128 kbps for voice, which is already excellent). MP3 export: VBR around 190 kbps via -q:a 2, which is broadcast-quality for voice and leaves no audible artifacts even on close listening.
My level meter is completely flat. What is wrong?
Four common causes. (1) Wrong input device selected, so pick the right one from the dropdown. (2) Mic muted at the OS level (Windows: Settings > System > Sound > Input; macOS: System Settings > Sound > Input). (3) Physical mute switch on a headset cable or earcup. (4) Browser denied permission silently, so refresh the tab and click Allow when prompted, or click the lock icon in the address bar and grant microphone access.
Can I record for an hour or longer?
Yes, but the blob lives in your tab memory, so very long recordings can get sluggish on lower-end machines. For anything past ~30 minutes a desktop recorder is more comfortable. This tool is built for sub-30-minute clips: voice memos, scratch takes, lecture segments.
Why does my MP3 sound different from the WebM?
Both are lossy encodings but they use different algorithms. At the bitrates we use, the difference is imperceptible on voice content, and A/B comparison on speech will not reveal which is which. If you do hear a difference, it is almost always slight high-frequency softening from MP3, which is harmless for spoken-word use cases.
Does the voice recorder work on iPhone and Android?
Yes on modern Safari (iOS 14.1+) and Chrome (Android). MediaRecorder is supported, the level meter works through Web Audio, and the MP3 export runs the same FFmpeg WebAssembly module, though older mobile devices may hit memory ceilings on longer recordings.
Why a browser voice recorder instead of a native app?
Speed and trust. There is nothing to install, no permission grab beyond the one mic prompt, and you can see in the network tab that nothing leaves your device. For a single-track scratch recording, opening a tab is faster than launching any DAW.
