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Convert TS to MP4 in your browser

Most .ts files hold H.264 video that MP4 can carry unchanged, so Video Mender rewraps them in seconds — no re-encode, no upload, and no quality loss.

Nothing is uploaded

Drop video files here

TS · MTS / M2TS

Choose video files to convert

Output format

Plays on effectively every browser, phone, TV and editor when it holds H.264 and AAC.

Video codec

The universal baseline. Hardware decoding exists on essentially every device sold since 2010.

How to size the output

A constant quality target. File sizes vary with how demanding the footage is.

Quality — 8 of 10

Resolution limit

Files smaller than the limit are left alone. Capping usually looks better than lowering the bitrate.

Frame rate

Audio

Fast rewrapCopy streams without re-encoding when the codecs already fit

Lossless and near-instant when it applies. It cannot reduce file size, so turn it off if you need a smaller file.

A transport stream is built for broadcast and streaming, where a player might join halfway through. It has no single header at the front; instead the structural information repeats throughout the file in small 188-byte packets. That design is excellent for live delivery and awkward for everything else, which is why editors and phones so often refuse .ts files.

The good news is that what is inside is usually modern. HLS segments and DVR recordings normally carry H.264 video with AAC audio, both of which MP4 accepts as-is. Video Mender detects that and rewraps rather than re-encodes, finishing in seconds even for a long recording.

When the stream carries MPEG-2 instead, as older broadcast recordings do, a re-encode is required — MP4 has no dependable way to hold MPEG-2. The queue labels which path each file takes before you start, so there are no surprises.

What this actually does to your file

Rewrap or re-encode

Rewrap runs when the stream holds H.264 or HEVC with AAC or AC-3 audio. MPEG-2 video and MP2 audio are decode-only here and force a re-encode.

Quality

Rewrapping an H.264 transport stream is lossless. MPEG-2 sources must be re-encoded, which is lossy — though MPEG-2 is so inefficient that the MP4 usually ends up much smaller at similar quality.

Broadcast recordings often contain several audio languages. Only the first audio track is kept.
A TS captured mid-broadcast can begin on a partial frame. The first fraction of a second may be dropped so the MP4 starts cleanly.
Timestamps in transport streams sometimes wrap around or jump. Where that causes audio drift, setting an explicit frame rate is the practical fix.

How to use this page

Add your .ts or .m2ts files.
Look for the "Fast rewrap" badge; MPEG-2 recordings will say "Re-encode" instead.
Keep MP4 as the output and press Start.
Download the results as they complete.

Where the result plays

Checked against the containers and codecs this page produces, stated conservatively.

Target	Works	Detail
Video editors	Yes	MP4 imports cleanly; TS import frequently gives audio with no video.
Phones	Yes	MP4 opens in the gallery. TS files generally will not.
Browsers	Yes	MP4 plays inline; a raw .ts file downloads instead.
Set-top boxes	Partly	These often play TS happily — converting is for everything else.

The formats involved

Format	Read	Write	What it is
TS	Yes	No	MPEG transport stream: a broadcast and HLS format built for streams that can be joined mid-flow, so it has no single global header.
MTS / M2TS	Yes	No	AVCHD camcorder recordings — an MPEG transport stream with 192-byte timestamped packets instead of the usual 188.
MP4	Yes	Yes	The MPEG-4 Part 14 container. It is a wrapper, not a codec — an MP4 usually holds H.264 or HEVC video with AAC audio.
MKV	Yes	Yes	Matroska. The most permissive common container: it will carry almost any codec, plus multiple audio tracks, chapters and subtitles.
MOV	Yes	Yes	Apple QuickTime. Structurally a close cousin of MP4, which is why MOV files can often be rewrapped to MP4 with no re-encode.

Tested limits

Real ceilings measured on real devices, not a marketing claim of unlimited.

Limit	Desktop	iPhone / iPad	Why
File size — rewrap	1.3 GiB	384 MiB	Rewrapping never decodes a frame, so it tolerates far larger files.
File size — re-encode	1.0 GiB	256 MiB	Decoding holds uncompressed frames in memory, which is the real constraint.
Clip length — re-encode	4:00:00	30:00	Beyond this, progress reporting and memory behaviour stop being dependable.
Resolution — re-encode	4096 × 2160	1920 × 1080	A 4K frame is about 12 MB decoded, before the encoder allocates anything.

If something goes wrong

The audio slowly drifts out of sync.

Transport stream timestamps can jump or wrap. Setting an explicit frame rate matching the broadcast standard — 25 fps in Europe, 30 fps in North America — normally resolves it.

The MP4 is much smaller than the TS.

Two possible reasons: transport stream packet overhead is significant and simply disappears in MP4, or the source was MPEG-2 and the H.264 re-encode is far more efficient.

Only part of the recording converted.

The stream is likely damaged at that point, which is common in over-the-air captures. Video Mender keeps the valid portion and reports the truncation rather than silently producing a short file.

Your video never leaves this device

This is a structural property of the application, not a policy we ask you to take on trust. There is no upload endpoint, no API route and no server action anywhere in the codebase, so there is nowhere for a video to be sent even by mistake.

Conversion runs in WebAssembly inside this browser tab. The engine is served from this domain and loaded only when you start a job.
The Content-Security-Policy restricts network connections to this origin, so the page is not permitted to contact a third party at all.
Nothing is stored. Close the tab and every queued file and finished output is gone — which is also why you should download results before you leave.
There are no accounts and no AI. Anonymous page views are counted — which page, roughly what country, what kind of device — and nothing whatsoever about your files.

The repository contains a test that fails the build if any media byte is passed to fetch, XMLHttpRequest, sendBeacon or a WebSocket. See the privacy page for how that is verified.

Questions

What is a .ts file?

An MPEG transport stream: a broadcast and streaming container made of small repeating packets so a player can start decoding from any point. HLS video and DVR recordings both use it.

Does converting TS to MP4 lose quality?

Not when the stream is H.264, which is the common case — the frames are copied unchanged. Only MPEG-2 sources need re-encoding, and those gain more from the efficiency than they lose to the generation.

Why will my editor not import the TS directly?

Because transport streams have no single index and can contain discontinuities. Editors want a file they can seek in reliably, which is exactly what the MP4 container provides.

Can I join several TS segments into one MP4?

No. Each queued file is converted on its own. Join the resulting MP4 files afterward in a video editor when you need one continuous video.

Is .m2ts the same thing?

Nearly. M2TS uses 192-byte packets with an extra timestamp field, and is what camcorders record. Both are handled here; see the MTS page for camcorder-specific detail.