MP4 to MP3 Converter

Convert MP4 to MP3 locally with FFmpeg. See output settings, step-by-step instructions, format limitations and common questions.

A practical guide

MP4 to MP3

Save the first audio track of a MP4 video as MP3. This route is useful when you need a recording without its picture, such as a voice track for listening or editing. The video must already contain audio; the converter cannot generate speech or restore a missing soundtrack.

Listen to or edit a video’s existing sound without the picture.
Export a selected passage rather than the entire recording.
Keep the source while preparing a separate delivery copy.

How to use MP4 to MP3

Select your MP4 files
Use Select File or drop supported MP4 files into the upload area. Each file creates a separate MP3 result. Check that the filename extension matches the contents and that the original opens correctly before adding a larger batch.
Choose the output settings
Open Options beside a selected file. Start time, Duration, Audio bitrate are available for this MP4 to MP3 operation. Save options to apply them to that file; other files in a batch can use different settings.
Convert to MP3
Select Convert to add the files to the local queue. Files run one at a time, with real progress where the engine provides it. You can cancel a queued or running job and retry a failed result after correcting its input or settings.
Download and check the result
When a file is finished, use Download to save the MP3 result. Use Download all for finished results on this converter page. Save downloads before the 30-minute temporary retention ends.

Understand the settings

Start time (seconds): Set where the conversion begins, measured in seconds from the start of the file. Default: 0.
Duration (seconds; 0 keeps remaining): Set how many seconds to convert. Use 0 to include the rest of the file. Default: 0.
Audio bitrate (kbps): Set the audio bitrate in kbps. Higher values usually increase sound quality and file size. Default: 192.

Start with one representative passage

For a recording longer than 20 seconds, set Start to 5 and Duration to 10 to export the passage from second 5 to second 15. Try the default bitrate first, then compare clarity and file size before reducing it. Use Duration 0 when you want the remaining recording.

Check your result

Play the saved file in the app you intend to use. Check the beginning and end, orientation, audio/video synchronisation and whether the required track is present. Only the first supported streams are used and metadata is removed. Inputs can be up to two hours; processing still has a job deadline.

Source and output formats

About MP4

Stores video and audio in a widely supported container. Local output uses H.264 video and AAC audio.

About MP3

Uses lossy audio compression for smaller files and broad compatibility. The selected bitrate affects size and sound quality.

What to know before you start

Only first video/audio streams; media is re-encoded, metadata removed.
Audio extraction requires an audio track. GIF has no audio.
Input duration limited to two hours; MP4/MOV/MKV use H.264/AAC, WebM uses VP9/Opus.
Up to 20 files per session, 100 MB per file and 200 MB per output. Processing has a 180-second job deadline.

MP4 to MP3: common questions

How do I convert MP4 to MP3?

Choose your MP4 files, review Options and the format notes, then select Convert. Download the finished MP3 copy and check it in your destination application. Each input is processed independently; the original file remains unchanged.

Can I extract audio from any video?

The video must contain an audio track. Local conversion extracts and re-encodes that track into the selected audio format.

Which settings can I change for MP4 to MP3?

Start time (seconds): Set where the conversion begins, measured in seconds from the start of the file. Default: 0. Duration (seconds; 0 keeps remaining): Set how many seconds to convert. Use 0 to include the rest of the file. Default: 0. Audio bitrate (kbps): Set the audio bitrate in kbps. Higher values usually increase sound quality and file size. Default: 192.

Will the result be smaller or better quality?

A successful MP3 conversion does not guarantee a smaller file or recovered detail. Container overhead, compression and the selected settings all affect output size. Check the saved result and keep the source if you might need a different export.

Why did my MP4 file fail?

Read the message beside the file. A mismatched extension, corrupt data, unsupported feature or resource limit can prevent conversion. Check that the source opens normally, try the default settings and retry. The app will not offer a successful download for a failed job.

Where are files processed and how long are they kept?

Your browser sends selected files to the local server on this computer. No external conversion service is used. Temporary job copies expire after approximately 30 minutes; remove or clear deletes them sooner. Originals and downloads you saved are not overwritten.