What is a TS file?

What TS is

TS is a stream format, written and read from front to back. It is used for broadcast and streaming.

The extension is .ts, and the full name is MPEG Transport Stream. Both matter less than what the file can hold, which is what the rest of this page is about.

Where TS came from

MPEG published it in 1995. The specification is ISO/IEC 13818-1.

A format that has been readable for that long is a format worth trusting with something you want back in ten years.

The specification is public

Anyone can implement it without asking permission or paying a licence, which is why it turns up in so many programs and why files written twenty years ago still open.

What else it can carry

TS can hold several audio tracks, subtitle tracks and a layout that lets it start playing before it has finished arriving.

That matters mostly when converting: whatever the target cannot hold is dropped, usually without a warning.

What opens TS

VLC and FFmpeg read it, and so do most programs of the same kind.

If a file will not open, the format is rarely the problem — it is more often that the program predates it. Converting to something older is the reliable way past that, and it is what the rest of this site is for.

Opening it in a browser

No browser reads it.

That is the single most common reason to convert it: not that the format is bad, but that the place you want to show the file cannot read it.

It is a delivery format

TS is meant to be handed over rather than worked in. Editing one is possible and rarely pleasant; the sane approach is to change the source and export again.

The facts, in one place

Formats worth considering instead of TS

• MPEG-4 Video
• Matroska Video