---
title: Convert video on a Mac: MOV, MP4, MKV, WebM
source: https://arazioformac.com/docs/convert-video
---

# Convert video

Pick the video up, hold <kbd>⇧</kbd>, let go toward the format.

**The one-gesture way**

1. Pick the file up in Finder, as if you were moving it.
2. Hold `⇧`. A ring of formats appears around the cursor.
3. Let go toward **MP4**. The new file lands beside the original.

MOV converts to seven formats — hold ⇧ and they appear around the cursor: GIF,
M4A, M4V, MKV, MP3, MP4, WebM.

Six actions work on any file at all — hold ⌃, including on files Arazio cannot
convert: AirDrop, Shelf, Copy, Move, Copy Path, Terminal.

That is the whole thing. It works on one file or four hundred, and
nothing is uploaded — the conversion happens on your Mac.

## The thing worth knowing: remuxing

A video file has two parts. The **container** is the box — MOV, MP4, MKV. The
**codec** is how the picture is actually encoded inside it — H.264, HEVC,
ProRes.

An iPhone MOV is almost always H.264 or HEVC. An MP4 holds H.264 or HEVC too.
So converting one to the other often means relabelling the box without touching
the video at all. That is a remux, and it is instant and completely lossless.

**Arazio remuxes whenever the streams allow it.** A MOV from your phone becomes
an MP4 in about a second, bit for bit identical inside. When the codec genuinely
cannot live in the destination container, it re-encodes using your Mac's
hardware encoders.

You do not have to ask for this or know which one happened. The difference
shows up as the job finishing immediately rather than taking a minute.

## When a re-encode is unavoidable

- **ProRes** — common from cameras and editors, very large, not valid inside
  an MP4.
- **HEVC where the destination wants H.264** — the container is fine, the
  recipient is not.
- **Making it smaller.** A remux does not change the size, because the video
  data is identical. Shrinking means re-encoding, by definition — use the
  **Compress** tool on <kbd>⌥</kbd>.

## Formats

MOV, MP4, MKV, WebM, M4V, AVI, MPEG, WMV, FLV and 3GP. Each has
[its own page](/docs/formats/mov) with exactly what it converts to.

Converting an old AVI, WMV or FLV is nearly always a re-encode, because the
codecs inside them are too old to put in a modern container.

## Getting the audio out

Hold <kbd>⌥</kbd> rather than <kbd>⇧</kbd> and release toward **Extract
Audio**. You get the soundtrack as its own file and the video is left alone.
[More](/docs/tools/extract-audio).

## Does it lose quality?

A remux: no, not a pixel.

A re-encode: yes, a little, always — video codecs are lossy and encoding an
already-encoded video compounds it. Do it once from the best source you have.