Supported formats
Output to MP4, MKV, WebM, or MOV. Input accepts almost anything FFmpeg can read.
H.264 / AAC
The most universally compatible format. Plays on every device, browser, and platform. Recommended for sharing, social media, and general use.
H.264 / AAC
Matroska container. Supports multiple audio/subtitle tracks. Great for archiving and media servers like Plex or Jellyfin.
VP9 / Opus
Open format designed for the web. Excellent compression with VP9. Ideal for web embedding and streaming.
H.264 / AAC
Apple's QuickTime format. Natively supported on macOS and iOS. Common output from iPhones and Final Cut Pro.
Various
Legacy format from the 1990s. Widely supported as input. We do not offer AVI as output — use MP4 instead for better compression and compatibility.
WMV / WMA
Windows Media Video. Still common on Windows systems. Accepted as input; compress to MP4 for better results.
H.263 / Sorenson
Adobe Flash Video. Legacy format. Accepted as input for converting old Flash videos to modern formats.
H.263 / AAC
Mobile video format from the 3GPP standard. Common on older phones. Accepted as input.
Note on input formats: Because smaller.video uses FFmpeg under the hood, it technically supports hundreds of input formats beyond this list. If FFmpeg supports it, it will work here. The formats listed are the most common ones you are likely to encounter.
Note on codecs: Output codecs are fixed per format. MP4/MKV/MOV use H.264 video with AAC audio. WebM uses VP9 video with Opus audio. These are the most compatible codecs for each container.