Online Video Conversion and Audio Extraction Tools

Convert your local video files: extract MP3 audio, convert MKV and WebM videos to MP4, convert MP4 videos to WebM, GIF or MOV. All processing happens in your browser.

Video to MP3

Upload your own MP4, MKV or WEBM video and extract the audio as MP3.

YouTube downloading is not supported. Conversions run entirely in your browser.

MKV to MP4

Convert MKV videos to MP4 using in-browser conversion (ffmpeg.wasm).

This runs directly in your browser. Large files may take longer to process.

MP4 to WebM

Convert MP4 videos to WebM format using in-browser conversion (ffmpeg.wasm).

This runs directly in your browser. Large files may take longer to process.

WebM to MP4

Convert WebM videos to MP4 format using in-browser conversion. Ideal for editing or sharing on devices that don’t support WebM.

Runs in your browser using ffmpeg.wasm. Large files may take time.

MP4 to GIF

Create animated GIFs from MP4 videos. Great for sharing short loops.

Uses ffmpeg.wasm in your browser. GIF size depends on video length and resolution.

MP4 to MOV

Repackage MP4 videos into the MOV container for use in editing or specific devices.

Uses ffmpeg.wasm to repackage MP4 files to MOV format in your browser. Large files may take longer.

GIF to MP4

Convert animated GIFs to MP4 videos for better compression and compatibility.

Uses ffmpeg.wasm to encode GIFs as MP4 in your browser. Output videos have dimensions divisible by two.

How to use these online video converters

Convert MP4, WebM, MKV, MOV, GIF and video to MP3 entirely in your browser—no uploads to a server.

Pick the tool that matches your goal: Video to MP3 for quick audio extraction, MP4 to WebM for smaller streaming-friendly files, MKV to MP4 for editor compatibility, or MP4 to GIF when you need a looping clip. These converters run with ffmpeg.wasm, so the raw video never leaves your device and conversions stay private.

For the fastest conversions, keep source files under a few hundred megabytes, close unused tabs, and avoid switching browser tabs while the conversion runs. Once processing finishes, your converted MP4, WebM, MOV, GIF, or MP3 file is ready to download immediately.

  1. Select the conversion you need and upload your MP4, MKV, WebM, MOV, or GIF file.
  2. Wait while the browser processes the video with ffmpeg.wasm. Progress appears in the output area.
  3. Download the converted WebM, MP4, MOV, GIF, or MP3 file and share it instantly.

Use Video to MP3 when you only need the soundtrack for podcasts, voice notes, or background music. Choose WebM output when you want a lightweight file for browsers that prefer royalty-free codecs, and choose MP4 or MOV when you need broad device support. GIF output is best for short, high-impact loops that are easy to embed.

These tools are ideal for creators, teachers, and teams who need quick edits without installing desktop software. Because conversions stay local, they also work well for confidential recordings or internal product demos that should not be uploaded to third-party servers.

Supported formats and best fits

  • MP4: broadest playback support on laptops, phones, and TVs.
  • WebM: lightweight for the web and great for Chrome, Firefox, and modern Edge.
  • MKV: use the MKV to MP4 converter to repurpose high-quality rips for editors.
  • GIF: keep clips under 10 seconds for shareable loops that load quickly.
  • Learn more: WebM Project overview.

Quality, compression, and audio

For MP4 and MOV outputs, keep the original resolution when quality matters; downscale to 720p to shrink file sizes. WebM outputs are efficient for social embeds and product docs. When extracting MP3, the tools preserve stereo audio; if you need voice clarity, record in mono and keep bitrates around 128–192 kbps for a good size-to-quality balance.

Privacy and reliability

Conversions run on-device via WebAssembly, so no media is sent to external servers. That makes these tools suitable for sensitive walkthroughs, classroom recordings, or client feedback. To avoid failed conversions, ensure your browser tab stays active, keep at least 500 MB of free memory available, and retry with shorter clips if a file is extremely large.

Need a different file type?

Check the navigation for PDF, image, audio, and data converters. If you rely on a format not listed here, reach out through the blog to request it—new video and audio presets are added frequently to keep up with modern codecs and workflows.