Frequently Asked Questions

How can you make this free?

All the processing is done on your local computer, and I host this on a server that was already running, fronted by a free Cloudflare account. Because your video isn't uploaded to the cloud, it doesn't cost much to run :) There are no ads, no accounts and no watermark added to your videos.

How private is it?

Your videos never leave your computer. Once the page is loaded, you can even disconnect your internet and the page will continue to work fine. I do have Google Analytics installed so I can see in aggregate what features people use, but that just gives aggregated statistics like "You had 10 visits from USA and 5 visits from the UK in the last 24hrs." The traffic is also going through Cloudflare so technically they could see your IP, but again, the video and video metadata don't leave your computer. The privacy page has the details.

Do the AI tools upload my video?

No. Blur Faces (YuNet face detection), Remove Video Background (MODNet and MediaPipe) and Auto Caption Video (Whisper speech recognition) run their models in your browser. The model files are downloaded from this site the first time you use one of these tools, and your browser keeps a copy, so later runs also work offline. No frames, audio or transcripts are sent anywhere.

How do I remove private details before sharing a video?

Prepare Video for Sharing does it in one pass. It can trim the video, remove the audio, strip identifying tags such as GPS location, device model and dates, blur or cover areas you mark, and fit a file size limit. It then re-reads the new file to check each step.

For a single job, Remove Video Metadata strips the tags without re-encoding, Blur Faces finds faces and blurs them, Blur Video blurs, pixelates or covers areas you draw, and Remove Video Background replaces what is behind a person with a colour, an image or a blur.

How do I send a large video without uploading it?

This site converts and prepares videos but doesn't send them. For sending, I built a separate site, SpectrShare, that transfers files directly between two browsers with no upload, no account and no size limit. Your browser tab needs to stay open until the transfer finishes. The file is sent exactly as it is, so run it through Compress Video or Remove Video Metadata first if you want it smaller or without its location tags.

Does it work offline? Can I install it?

Yes. You can install it from your browser as an app. After your first visit the pages are stored on your device. The FFmpeg engine and the AI models are stored the first time a tool needs them, and from then on those tools work without a connection too.

Why are some conversions super fast and others super slow?

Behind the scenes I have a couple of different pathways for the transcodes. The primary path is using Mediabunny which taps into your browsers WebCodec and WebGL support. This is very fast, but has limited format support depending on your browser. Safari in particular has quite limited support.

If your selected workflow is not supported by your browsers built-in tools, we revert to using ffmpeg.wasm - this has very wide codec support, but is entirely CPU based and currently single threaded as the multithreaded version is buggy. This results in much slower conversion times than the other pathway.

Which codecs and containers are supported by this tool?

Output containers

MP4, WebM, MOV, MKV, AVI and animated GIF

Output video codecs

H.264 (AVC), H.265 (HEVC), VP8, VP9 and AV1

Output audio codecs

AAC, MP3, Opus and Vorbis, or no audio; Extract Audio also writes lossless WAV or FLAC

Accepted input files

MP4, M4V, MOV, WebM, MKV, AVI, WMV, FLV, 3GP, MPEG-TS (TS, MTS, M2TS) and MPEG-PS (VOB, MPG)

H.264 and VP8 can always be encoded: with WebCodecs (Mediabunny) where your browser supports it, otherwise with FFmpeg.wasm. VP9, AV1 and H.265 are encoded only through your browser's WebCodecs support, so if your browser can't encode them the tool tells you and suggests a codec that works. GIF and AVI output always use FFmpeg.wasm, which can also read many input codecs your browser can't decode itself. MP3 audio in an MP4, MOV or MKV video is encoded in the browser too (WebCodecs or a built-in WebAssembly MP3 encoder); WebM cannot hold MP3.

The supported formats page lists every container and codec the app reads, which engine handles each, what plays where, and what your browser can decode and encode.

How big a file can I convert?

There is no fixed file size limit. Files over 1 GB show a warning, because processing them in a browser is slow and uses a lot of memory. How large an output can be depends on the browser: the output is normally held in memory until you download it, so very large outputs need a browser that can save straight to a file on your disk (desktop Chrome or Edge). If a conversion is too large for this browser, the tool says so before it starts.

If that's too slow for you or your files are bigger, there's free software you can run on your computer that will be much faster than this web based version and handle much larger files. I recommend Handbrake.