Where HEVC causes problems
Windows doesn’t always include an HEVC decoder, many browsers can’t play HEVC in a web page, and plenty of editing and upload tools reject it outright. If a video shows audio with a black screen, or won’t open at all, HEVC is a likely cause.
H.264 is supported by essentially every device made in the last fifteen years. The trade-off is file size: an H.264 file at the same quality is typically 30–50% larger than HEVC.
Keeping 4K footage
This tool defaults to 2160p, so 4K footage stays at full resolution. Converting 4K in a browser is demanding and can take several times the length of the clip. If you only need the video for a phone or a web page, choose 1080p for a much faster conversion and a smaller file.
High-frame-rate footage, such as 60 or 120 fps action-camera clips, keeps its original frame rate.
Sharing footage with people who can’t open it
If a friend says your video plays with sound but no picture, or a client can’t open drone footage on their work laptop, send them an H.264 copy. It’s the safest choice when you don’t know what device the other person uses.
Private by design
ClipFit processes your video inside your browser using FFmpeg compiled to WebAssembly. The file is never uploaded, so there’s no waiting for transfers and no copy left on a server. Once you close the tab, nothing remains.
Questions
How do I know if my video is HEVC?
On a Mac, choose Get Info on the file and look for “HEVC” under Codecs. On Windows, the Properties dialog or a player like VLC (Tools → Codec Information) will show H.265 or HEVC.
Will I lose quality?
Any re-encode loses a small amount of detail, but ClipFit uses a high-quality setting that is very hard to tell apart from the source at normal viewing sizes.
What about 10-bit or HDR footage?
It is converted to standard 8-bit H.264. Colours in HDR footage may look flatter, since most H.264 players don’t support HDR.