Extract Audio from Video — Free Online Audio Extractor
Pull the audio track out of any video file and save it in the format you need — right in your browser, with nothing uploaded to any server. Alfreto's audio extractor uses FFmpeg.wasm to separate the audio from MP4, WebM, MOV, MKV, and AVI files and export it as MP3, WAV, AAC, OGG, FLAC, or OPUS. Choose your output format and bitrate, then download the result in seconds. No account, no watermark, completely free.
Ready.
How to Extract Audio from a Video File
Alfreto's Extract Audio tool separates the audio track from a video file and saves it as a standalone audio file in the format you choose. The entire process runs locally in your browser using FFmpeg.wasm — the same open-source engine behind professional video editing software. No file is ever uploaded to a server, and there is no account or subscription required.
Step 1 — Upload Your Video
Click Choose Video or drag and drop your video file into the upload area. The tool accepts MP4, WebM, MOV, MKV, and AVI. Once the file is loaded, a video preview appears on the right so you can confirm you have the right file. The video's duration and file size are also displayed automatically.
Step 2 — Choose Your Output Format
Select the audio format you want to save the extracted track as:
- MP3 — The most universally supported format. Works on every device, media player, car stereo, and streaming app. The best default choice for most people.
- AAC — Better compression than MP3 at the same bitrate. The default audio format on iPhones, iPads, and iTunes. Widely supported on Android and web browsers.
- WAV — Uncompressed, lossless audio. Produces the largest files but preserves every detail of the original recording. Ideal for professional editing workflows.
- FLAC — Lossless with compression. Preserves full audio quality while producing smaller files than WAV. The best choice for archiving high-quality audio.
- OGG (Vorbis) — Open-source format with efficient compression. Commonly used in web games, Linux systems, and open-source media players.
- OPUS — A modern codec with excellent quality at very low bitrates. Ideal for voice, streaming, and web audio where bandwidth matters.
Step 3 — Set the Bitrate (Lossy Formats)
For lossy formats (MP3, AAC, OGG, OPUS), select a bitrate from the dropdown. Higher bitrate means better audio quality but a larger file. Lower bitrate means a smaller file but more compression artifacts. 192 kbps is the recommended default for music. For voice recordings, lectures, and podcasts, 64–96 kbps is sufficient and keeps file sizes small. WAV and FLAC are lossless — the bitrate setting is ignored for these formats.
Step 4 — Extract and Download
Click Extract Audio. On first use, the browser downloads the FFmpeg engine (~10 MB) — a one-time step that is cached automatically. A progress bar shows real-time status. When extraction is complete, the extracted audio appears in the output preview panel so you can listen before downloading. Click Download to save the file to your device.
When Do You Need to Extract Audio from a Video?
- Save a song from a music video — Download a video and extract just the audio track as an MP3 to play offline.
- Get audio from a lecture or webinar — Extract the audio from a recorded meeting or online class to listen on the go.
- Create a podcast from a video recording — Record a video interview, then extract and compress the audio for podcast distribution.
- Separate audio for editing — Pull the audio track from a video clip before importing it into a DAW or audio editor.
- Build a ringtone — Extract audio from a video, then use the Audio Toolkit to trim the exact segment you want.
- Archive audio privately — Since nothing is uploaded, this tool is safe for extracting audio from sensitive or private recordings.
Frequently Asked Questions
Is my video uploaded to a server?
No — never. All processing happens entirely inside your browser using FFmpeg.wasm, a WebAssembly build of the professional FFmpeg engine. Your video file is read from your device's local memory, processed there, and the audio output is written back to your device. Nothing is transmitted over the internet during this process.
Which video formats can I extract audio from?
The tool supports MP4, WebM, MOV, MKV, and AVI as video input formats. These cover the vast majority of video files you are likely to encounter — from smartphone recordings and downloaded videos to screen recordings and professionally produced content.
Which audio output formats are available?
You can save the extracted audio as MP3, AAC, WAV, OGG, FLAC, or OPUS. MP3 is the most universally compatible. AAC is preferred for Apple devices. WAV and FLAC are lossless and ideal for editing or archiving. OGG and OPUS are open-source codecs well suited for web use and streaming.
What bitrate should I choose?
For music and general audio content, 192 kbps is the recommended default — it provides excellent quality with a manageable file size. For voice-only content like podcasts, lectures, interviews, or voice memos, 64–96 kbps is fully sufficient and keeps files very small. Use 256–320 kbps if you need near-lossless quality for professional or archival use. WAV and FLAC ignore the bitrate setting since they are lossless formats.
Can I extract audio from an MP4 file?
Yes. MP4 is fully supported as an input format. Load your MP4 video, select an output format (MP3 is usually the best choice for compatibility), set your bitrate, and click Extract Audio. The process completes in your browser with no upload required.
Can I extract audio from an MKV or MOV file?
Yes. Both MKV (Matroska) and MOV (QuickTime) are supported input formats. MKV files are common for downloaded movies and TV shows, while MOV files are typically recorded on iPhones and Mac computers. Regardless of the input container, the audio track is extracted and saved in your chosen output format.
Does extracting audio affect the quality?
If the original video contains a lossy audio track (such as MP3 or AAC at a given bitrate), re-encoding it to another lossy format will result in a small quality reduction — a process called generation loss. To avoid this, either extract to a lossless format (WAV or FLAC) or match the output bitrate to the original. If the source audio is already lossless (e.g., PCM in an AVI or MKV), extracting to WAV or FLAC preserves the full original quality.
Is there a file size limit?
Since processing happens locally on your device, there is no server-imposed file size limit. Practical limits depend on your device's available memory. Most devices handle video files up to 1–2 GB without issues. For very large files (above 2 GB), consider splitting the video first or using a desktop application for the extraction.
Why does it take time on the first use?
On first use, your browser downloads the FFmpeg.wasm engine files (approximately 10 MB) from a CDN. This is a one-time download that is automatically cached in your browser. Subsequent uses in the same session start almost immediately, and future sessions benefit from the cached engine files.
Which browsers are supported?
The tool works in all modern desktop and mobile browsers: Google Chrome, Microsoft Edge, Mozilla Firefox, and Safari. No browser extensions or plugins are required. For the smoothest experience, use the latest version of Chrome or Edge on a desktop or laptop computer.
What if the video has multiple audio tracks?
FFmpeg automatically selects the default audio stream, which is typically the main audio track. For most standard video files, this is the correct and only track. Support for selecting a specific audio stream from multi-track files (e.g., multilingual films) may be added in a future update.
Can I use this tool on my phone?
Yes. The tool runs in any modern mobile browser, including Safari on iOS and Chrome on Android. However, because mobile devices have less RAM than desktop computers, very large video files may process more slowly or reach memory limits on older phones. For large files, a desktop browser is recommended.
Why Use Alfreto to Extract Audio?
Most online audio extractors work by uploading your video to a remote server, processing it there, and sending back a download link. That approach creates privacy risks, file size limits, and dependency on server capacity. Alfreto processes everything locally — your video never leaves your device.
Your video file is never uploaded. There is no way for anyone — including Alfreto — to access, store, or view your files. This makes the tool safe for sensitive recordings, private meetings, or confidential content.
Server-based tools typically cap uploads at 100–500 MB. Because Alfreto processes files locally, your device's memory is the only practical limit — meaning most files of any reasonable size are supported.
Powered by FFmpeg — the industry-standard open-source multimedia engine used by YouTube, VLC, Handbrake, and countless professional tools. You get broadcast-quality audio extraction in a simple, free browser interface.
After the FFmpeg engine is cached on first use, the tool works without an active internet connection. Extract audio from videos anywhere — on a plane, in a remote location, or anywhere else without reliable Wi-Fi.