Simple online media conversion

Convert your video.
Keep it simple.

Justvert is a clean online video converter for changing MP4, MOV, WebM, MKV and other common media files into the format you actually need.

Drop a video file here

or choose a file from your device

MP4 · MOV · WebM · MKV · AVI · M4V and more
Built for private file handling Fast conversion workflow No software to install

Popular video converters

Go straight to the conversion you need. Dedicated converter pages make common format changes faster and easier to understand.

MP4→MP3

MP4 to MP3 Converter

Extract the soundtrack from an MP4 video and save a clean MP3. Justvert uses audio transcode so the video track is dropped and only the sound is written out.

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MOV→MP4

MOV to MP4 Converter

Turn a QuickTime MOV into a widely compatible MP4. When the source is H.264, Justvert remuxes the streams instead of re-encoding them.

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WEBM→MP4

WebM to MP4 Converter

Change a WebM file into MP4 for easier playback and sharing. VP9 sources use the WebCodecs hardware path when available.

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MKV→MP4

MKV to MP4 Converter

Change MKV video into MP4 for wider compatibility. H.264 plus AAC sources are remuxed; other codecs fall back to FFmpeg WASM.

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MP4→GIF

MP4 to GIF Converter

Create a shareable GIF from an MP4 clip. GIF encoding uses FFmpeg WASM for the widest compatibility.

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VIDEO→MP3

Video to MP3 Converter

Turn common video formats into an audio-only MP3. Justvert detects the source, then runs an audio transcode.

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Convert a video in three steps

No editing timeline, complicated settings or software installation. Just choose a file, select a format and convert.

01

Choose your file

Add a video from your device. Justvert can identify common video and audio formats automatically.

02

Pick an output format

Choose MP4 for compatibility, MP3 for audio, WebM for the web, or another format suited to your workflow.

03

Convert and save

Start the conversion, then save the finished file when it is ready. Processing stays in the browser.

Formats people actually use

Justvert focuses on practical video and audio formats instead of burying simple conversions under hundreds of obscure choices.

MP4 ConverterMOV ConverterWebM ConverterMKV ConverterAVI ConverterMP3 ConverterWAV ConverterGIF Converter

A video converter that stays out of your way

Online video conversion should be straightforward. Justvert is designed around the job users came to do: change a media file from one format to another without navigating a full video editor.

The homepage works as a broad online video converter, while dedicated pages cover specific searches such as MP4 to MP3, MOV to MP4 and WebM to MP4. That keeps each conversion page focused on one task and makes it easier to explain format compatibility, quality choices and use cases clearly.

Video converter FAQ

What video formats can I convert with Justvert?

Justvert supports common formats such as MP4, MOV, WebM, MKV, AVI and M4V, along with audio outputs including MP3 and WAV. GIF is available for short clips. Each dedicated converter page lists the inputs and outputs that page is built for.

Do I need to install software to convert a video?

No. Justvert is an online video converter. Open a modern web browser, drop a file, and convert. There is no desktop app or browser extension to install.

What is the best format for a converted video?

MP4 is the safest general-purpose choice because phones, browsers, editors and social platforms all play it. WebM is useful for websites. MP3 is the right output when you only need the soundtrack.

Can I convert MP4 to MP3?

Yes. The MP4 to MP3 converter extracts the soundtrack from an MP4 video and saves it as an MP3. Use Video to MP3 when the source is MOV, WebM, MKV or another common video format.

Will converting a video reduce its quality?

It can, if the file has to be re-encoded. Compatible H.264 plus AAC streams can be remuxed into MP4 without touching the pictures or the sound. WebCodecs and FFmpeg paths re-encode and may introduce some quality loss depending on the source and output size.

Does Justvert upload my files to a server?

No. Conversion runs locally in your browser. The chosen file is read on the page, processed by remux, WebCodecs or FFmpeg WASM, then written back with a WritableStream or a download. Source files are not uploaded to a Justvert conversion server.

Is Justvert free to use?

Yes. Justvert is a free online video converter. You can convert common video and audio formats in the browser without creating an account.

Which browsers does Justvert work in?

Justvert works in current versions of Chrome, Edge, Firefox and Safari on desktop. Mobile browsers can convert smaller files. Hardware encode with WebCodecs depends on the device and the browser.

Is there a file size limit?

There is no fixed Justvert upload cap because files stay on your device. Very large files are limited by the memory available to the browser. If a conversion runs out of memory, try a shorter clip or a smaller output size such as 720p or 480p.

What is remux and when does Justvert use it?

Remux copies existing video and audio streams into a new container without re-encoding. Justvert uses the COPY REMUX path when a MOV or MKV already contains H.264 video and a compatible audio track, then writes an MP4. That is the fastest path and keeps the original quality.

How does Justvert choose a conversion path?

The Media Analyzer inspects the file. The Strategy Engine then picks COPY REMUX for compatible H.264 streams, WebCodecs when the GPU can transcode, or FFmpeg WASM when a legacy container or codec needs a compatibility fallback.

Do I need an account to convert a file?

No. Open the converter, choose a file and convert. Justvert does not require a sign-up for the default conversion workflow.

Can I convert a video to GIF?

Yes. The MP4 to GIF converter and the GIF converter page turn a short video clip into an animated GIF. GIF encoding uses FFmpeg WASM.

Does Justvert work on iPhone and Android?

Yes, in a modern mobile browser. Smaller files convert more reliably on phones because browser memory is limited. For long 1080p files, a desktop browser is usually more comfortable.