Understanding the file you end up with

The container is the box and the codec is the packing

A video file has two parts worth naming. The container is the outer format, and it is what the file extension refers to: MP4, WEBM, MKV. It holds the picture track and the sound track together and keeps them in step.

The codec is the method used to compress each track before it went into the box. H.264 and VP9 are picture codecs; AAC and Opus are sound codecs. Two files can share a container and hold different codecs inside, which is why a file with a familiar extension sometimes behaves unfamiliarly.

Why every row carries two numbers

Each row in the results list shows a resolution and a size, and the pair is what makes the row meaningful. The resolution is how many pixels the picture has. The size is how many megabytes those pixels take up once compressed.

The two are related but not locked together. A row at the same resolution as its neighbour can be noticeably larger because it was encoded at a higher bitrate, which means more data spent per second of video. More data per second gives a cleaner picture in fast motion, and it is invisible in a still shot.

• Same resolution, larger size: more data per second, which shows in scenes with a lot of movement.
• Lower resolution, smaller size: fewer pixels, and the file finishes transferring sooner.
• The size figure is what counts against the 150 MB single-file ceiling on free use, not the resolution figure.

What the file is when it lands

The file that arrives is the encoding the source published, in the container the source published it in. Nothing is re-packed and nothing is re-compressed on the way to you, so the picture you get is the picture that was there.

That has a practical consequence. If the rows offered are WEBM, the file that saves is WEBM, and there is no MP4 version of it to ask for. Converting between containers is a separate job that this page does not do.

Playing it once before you need it

Check the file the day you save it, not the evening you intend to watch it. The check takes a minute and settles whether the container and codecs suit the software you plan to use.

Open the file, let a few seconds play, then drag the position marker to the middle and to the end. Picture and sound at all three points means the file is complete.

• Sound but a black picture: your player handles the container and not the picture codec inside it.
• Picture with no sound: the same problem on the audio side, or a source that publishes its sound as a separate row.
• Playback that ends abruptly well before the stated length: the transfer was interrupted, so delete the file and run the row again.

When a player refuses the file

A refusal is about the software, not the file. Built-in players on phones and desktops support a short list of codecs, and a file outside that list opens to a blank window or an error.

Try the file in a second player before concluding anything is wrong with it. A player with broad codec support opens material the default one will not, and the same file that failed a moment ago plays normally.

Size, the free tier, and where the copy lives

Single files under 150 MB download on a free account, and free accounts get three downloads a day. Pro removes the daily count, removes the size ceiling and removes the advertising.

Wherever it came from, the saved copy is on your own device once the transfer finishes. Prepared files expire on a short timer on our side, so start the transfer while the page is open rather than coming back to it later.

Related pages

• Downloading from this host generally
• MP4 as a container and what to do about WEBM
• Resolution against bitrate when choosing a row
• Checking and filing the saved file
• The free size ceiling explained