4. Convert & split a video in your browser

Uploads accept MP4, MOV, WebM, AVI, MPEG, FLV, WMV and 3GPP, up to the per-file size and length limits shown on the upload screen. Two things used to be dead ends: a .mkv file, and a file over the cap. Both now have an in-browser fix that runs on your machine before anything is sent anywhere.

Convert: MKV → MP4 without re-encoding

When you drop an .mkv file, the app offers Convert in your browser. This is a remux — the video and audio streams are copied into an MP4 container as-is. Nothing is re-compressed, so quality is unchanged and it is fast (seconds to a minute or two, depending on the file). The converted MP4 then goes through the normal upload flow.

Drop the file on the Analyze an Uploaded Video tab.
When the format notice appears, choose Convert in your browser.
Wait for the progress bar, then tick the rights box and add the video as usual (Chapter 3).

[SCREENSHOT: the format notice with the Convert in your browser button and its progress bar]

If a file's streams can't be placed in MP4 (an unusual codec), the converter says so; export an MP4 from your editor instead.

Split: bring an oversized file under the cap

When a file is over the size or length limit, the app offers Split into parts. It cuts the file into consecutive parts that each fit under the cap, still in your browser, and adds each part to the batch as its own video. Every part gets its own report; timestamps in each report count from the start of that part. Files larger than the upload limit are split into sequential parts so each part can be analyzed.

[SCREENSHOT: the over-limit notice with Split into parts, and the resulting parts listed in the batch]

Where the work happens

Converting and splitting run entirely in your browser. No file is uploaded until you approve the batch, and the upload itself still goes straight from your browser to Google (Chapter 21). Large files need memory: on a phone or a low-memory laptop, close other tabs first.

Questions people ask

Can I analyze an MKV file?

Yes. Drop it on the upload tab and choose Convert in your browser; it becomes an MP4 with identical quality, then uploads normally.

Does converting reduce quality?

No. It is a container change (remux), not a re-encode. Frames and audio are byte-for-byte the same.

What if my video is longer than the limit?

Choose Split into parts. Each part is analyzed as its own video with its own report.

Is my file sent anywhere while it converts?

No. Conversion and splitting happen on your device; upload only starts when you add the videos to the batch.

Independent AI-generated analysis. Not affiliated with or endorsed by YouTube. May contain errors.