Video to MP3

Extract the audio in three steps

1. Choose one local video, up to 512 MiB, and select Inspect audio. The tool checks its actual container and audio streams; a filename extension alone does not establish support.
2. Choose a stream when several are available, select 128, 192, 256 or 320 kb/s, and choose the channel policy. Surround input needs an explicit mono or stereo downmix choice.
3. Select Convert to MP3. The complete selected audio is encoded and checked before its result player and Download MP3 action become available. Cancel never creates a partial successful track.

What is included in your MP3

MP4, MOV, Matroska and WebM are containers, not promises about their audio codecs. Supported files need a real video stream and an admitted audio stream. This tool does not fetch online video links or convert audio-only files.

One audio stream is included. With several streams, choose explicitly rather than assuming the default language or commentary track is the one you want. A stream can itself contain mono, stereo or several surround channels.

The complete decoded audio is normalized to start at time zero and resampled to 48 kHz. Keep mono/stereo preserves those channel counts; surround conversion requires a declared downmix. A longer video does not add silence to the chosen audio.

The bitrate is an encoder setting, not a quality score or a promise of file size. Re-encoding is lossy, and a larger bitrate cannot recover information that was missing from the source. Original tags, chapters and artwork are not copied; technical gapless information remains.

Checks that help explain the result

At 48 kHz, 60 seconds contains 2,880,000 sample frames. A stereo sample frame has one sample for each channel; it is not twice as long as mono.

At 192 kb/s, a 60-second track has 1,440,000 nominal audio payload bytes. Headers and encoder framing mean this is not a promised download size. The result shows the actual verified bytes.

A video can last 10 minutes 10 seconds while its chosen audio contains 10 minutes of decoded samples. The MP3 result uses the checked audio duration, not the longer container label or a short preview.

Format and processing limits

Support covers documented local MP4/MOV-family and Matroska/WebM video with admitted AAC, MP3, Opus, Vorbis, FLAC, ALAC or specified PCM audio. Protected, corrupt, warned, externally referencing and unsupported inputs stop with an explanation rather than a repaired-looking result.

One file may be at most 512 MiB. The chosen audio may contain at most 20 minutes of verified 48 kHz samples, with source rates from 8 to 96 kHz and recognized layouts through eight channels. Unknown duration is checked during complete processing, not treated as unlimited.

Inspection has a 90-second deadline and complete conversion a 900-second deadline, including checking. MP3 output is capped at 64 MiB; native allocation, stream, counter and filesystem limits also apply. These limits do not guarantee browser-wide peak memory or completion on every device.

A playable beginning, a percentage indicator or an encoder success code alone does not prove completion. The full output is decoded and its gapless sample count and MP3 framing are checked before download. Some players handle encoder delay and padding differently.

The tool does not trim, normalize loudness, preserve surround channels, keep original compressed bytes or download videos from websites. Keep the source when you need its original quality, timing, metadata or other streams. A refusal does not prove your source is damaged.

Local processing without a saved media history

The tool adds no media upload, saved history or input-bearing link; only reviewed static engine assets may load. Cancel terminates its active worker and releases references best-effort, but downloads, host file operations, browser memory, extensions and existing site services are not covered by a forensic-erasure or universal security promise.