Video Converter

About the Free Online Video Converter

This free online video converter changes a video file's format — from MP4 to WebM, MOV to MP4, MKV to MP4, or into an audio file like MP3 or WAV — without uploading anything. The whole conversion runs inside your browser tab, so your video never leaves your device. Supported output formats include MP4, MOV, WebM, MKV, plus MP3, WAV, OGG, FLAC, and AAC for audio extraction.

Key Features

• Nine output formats. Four video containers (MP4, MOV, WebM, MKV) and five audio formats for extracting the soundtrack (MP3, WAV, OGG, FLAC, AAC).
• Fast remuxing when possible. If the input video already uses a codec compatible with the target container, the conversion finishes in seconds — the tool repackages the streams without re-encoding them.
• Automatic re-encoding when needed. When codecs are incompatible (for example, H.264 inside a WebM container), the tool re-encodes transparently using your browser's built-in video engine.
• Audio extraction in one click. Pick any audio format and the tool drops the video track and outputs just the sound — ideal for turning a recording into a podcast or music clip.
• Fully client-side. No uploads, no accounts, no watermarks, no file-size meter on a server. The only limit is your device's memory.
• Live progress and cancellation. A progress bar shows elapsed time; a cancel button stops the conversion instantly if you change your mind.

How Does a Video Converter Work?

Every video file has two layers: the container (the .mp4 or .webm wrapper that holds the streams) and the codecs inside it (H.264, VP9, AAC, Opus, and so on). Changing format means changing the container — and sometimes the codecs.

When the codecs already match the target container, the converter performs a remux: it copies the encoded video and audio bitstreams into a new container without touching the data. Remuxing is near-instant because no pixels get recomputed. A 10-minute H.264 video in a MOV file can be rewrapped as MP4 in well under a second.

When the codecs don't match — for example, converting H.264 video into a WebM container that only accepts VP8, VP9, or AV1 — the video converter falls back to transcoding. It decodes the original frames, re-encodes them with a compatible codec, then muxes the result. Transcoding takes longer because every frame is processed, but the tool handles the switch automatically based on the format you pick.

How to Use the Video Converter

1. Drop a video file onto the upload area or click to browse. Most video formats are supported, including MP4, MOV, WebM, MKV, AVI, and more.
2. Pick the output format. Video formats sit in the top group; audio formats (for extracting the soundtrack) are below.
3. Click Convert Video. The progress bar shows the percentage complete and elapsed time.
4. Preview the result in the built-in player, then click Download to save the converted file to your device.

Common Use Cases

A video converter handles many everyday tasks:

• Making iPhone recordings compatible with older software. iPhone videos in .mov are easy to convert to .mp4 for broader tool support.
• Embedding video on the web. Convert MP4 to WebM for smaller, faster-loading HTML5 video on modern browsers.
• Extracting audio from interviews, lectures, or gameplay clips. Save just the soundtrack as MP3 or WAV for podcasting, transcription, or music production.
• Sharing MKV files with people who can't play them. Convert MKV to MP4 so the video plays natively on iPhones, default Windows players, and most social platforms.
• Archiving in a lossless audio format. Convert a video soundtrack to FLAC to keep the audio intact for later editing.

Privacy: Your Video Never Leaves Your Device

The video converter runs entirely in your browser using the WebCodecs API and the mediabunny library. No footage is uploaded to any server, no account is created, and no copy is stored anywhere outside your device. This makes the tool safe for confidential footage — interviews, internal demos, medical recordings, or personal videos — without having to trust a third party.

Frequently Asked Questions

Is my video uploaded to a server?

No. The conversion runs entirely in your browser. Your video file is never sent over the network, and no account is required. You can verify this yourself by opening the Network tab in browser devtools before converting — you won't see any request containing the video data.

How do I convert MOV to MP4 online for free?

Drop your MOV file into the upload area, select MP4 as the output format, and click Convert Video. Because most MOV files already contain H.264 video and AAC audio — both of which also live happily inside MP4 — the conversion usually finishes in seconds without re-encoding.

How do I extract audio from a video?

Load the video, then pick any audio format from the second group (MP3, WAV, OGG, FLAC, or AAC). The converter discards the video track and outputs just the audio. MP3 is the most universal choice; WAV and FLAC are lossless if you need the highest audio fidelity.

Why is the conversion sometimes instant and sometimes slow?

The converter remuxes when codecs are compatible and re-encodes when they aren't. Remuxing only rewrites the container and finishes almost instantly. Re-encoding processes every frame and takes time roughly proportional to the video's duration. A longer re-encoding run is normal, not a bug.

Is there a file-size limit?

Input files up to 2 GB are accepted. The practical ceiling is your device's available memory, since the converted output is built in-browser before download.

Which browsers are supported?

The tool relies on the WebCodecs API. Chrome 94+, Edge 94+, Safari 16.4+, and Firefox 130+ all support it. If your browser is missing WebCodecs, the tool displays a notice asking you to switch browsers rather than failing silently.

Related Tools

Need to reduce file size as well as change format? Use the Video Compressor to tune quality and bitrate. To shorten a clip before or after converting, try the Video Trimmer. To record a new video directly in your browser, the Screen Recorder captures screen, camera, and audio and saves straight to disk.