Upload an MP4 file and convert it to MOV. When the codecs already fit the target container, the conversion is lossless and near-instant; otherwise the video is re-encoded.
Your file never leaves your device. All processing happens right in your browser, and nothing is uploaded to a server.
MP4 and MOV share their underlying structure, so this conversion is usually a lossless repackage: identical video and audio, new QuickTime wrapper, near-instant completion.
Older versions of Final Cut and some Apple-centric pipelines prefer or require MOV input, and certain legacy macOS tools behave better with it. When a spec sheet says QuickTime, this gets you there without touching quality.