Why MP4 is the right default
MP4 is the universal video container. Every smartphone made in the last decade plays MP4. Every TV that takes a USB stick plays MP4. Every video editor opens MP4 directly. Every social platform accepts MP4 uploads. Every messaging app preserves MP4 inline. There is no “will this work?” question to answer.
Some downloaders default to WebM (Google’s preferred container for AV1) which is technically a smaller file at the same quality, but WebM playback breaks on iOS, on older Windows machines, and inside many editing tools. MP4 is the safe default; we package every download as MP4 with H.264 or AV1 inside, depending on which YouTube serves.
Quality range supported
Every resolution YouTube hosts becomes an MP4 row in the picker:
- 4320p (8K) — rare, but present on drone footage and some music videos
- 2160p (4K) — common on professional channels
- 1440p — QHD, between 1080p and 4K
- 1080p — Full HD, the most common
- 720p — HD, smallest of the “watchable” tier
- 480p, 360p, 240p, 144p — legacy / mobile / accessibility
Each row shows the actual file-size estimate so a 5-minute video at 1080p (~90 MB) is clearly distinct from the same video at 4K (~600 MB).
No re-encode, no quality loss
A re-encode is when the tool decodes the video, then encodes it back to a new MP4 at some bitrate. This loses quality — the second encode is always lossier than the source. Many online “YouTube to MP4” tools do this on a server they rent, because that’s the cheapest way to combine the separate video and audio streams YouTube serves above 720p.
VidPickr never re-encodes. The video bytes you save are the video bytes YouTube serves — identical. The audio bytes are the audio bytes YouTube serves. The MP4 container around them is built locally with mp4-muxer (a real ISOBMFF muxer running in your browser), not a transcoder. What lands on disk has exactly the same image quality as the YouTube source.
MP4 vs WebM: which to actually pick
YouTube ships some videos in both MP4 and WebM containers. When that happens, here is the rule of thumb:
- Pick MP4 for anything that needs to play on iOS, in older editors, or inside legacy social apps.
- WebM is fine for modern browsers (Chrome, Edge, Firefox), modern editors (Premiere 24+, Resolve 18+), and Android — and gives you ~30% smaller files.
We default to MP4 because the “will this work tomorrow on the device I want to play it on?” answer is more reliably yes for MP4. WebM is available too if you specifically pick it.