What is a QT file?
QT stands for QuickTime movie. It was created by Apple and first released in 1991. QT is the original extension of QuickTime movies, from the days when Mac files had no extensions and Windows needed one. A QT file is the same container as a MOV, so renaming it to .mov is often all a program needs.
MOV is the same format under another extension.
| Type | video |
|---|---|
| Compression | Lossy |
| Usually contains | H.264, MPEG-4, Sorenson or other QuickTime codecs with AAC or other audio |
| In a browser | plays in Safari when the video inside is H.264; other browsers usually download it |
| Common uses | QuickTime movies from older Macs, CD-ROMs and early web video |
| MIME type | video/quicktime |
Which format should you convert QT to?
- QT to MP4 to play on any phone, computer or TV, or to upload to YouTube and social media.
- QT to MOV to edit in iMovie or Final Cut Pro on a Mac.
- QT to MP3 to keep only the soundtrack, for music or a podcast.
- QT to GIF to share a short silent clip that loops anywhere.
QT is already lossy, so converting it to a lossless format makes the file bigger without improving it; pick a lossless target only if a program requires one.
How to open a QT file
Whether a QT file opens with a double click depends on the device. Here is what works on each, without buying software:
| Windows | Films and TV and Media Player open the common formats; VLC opens almost any video file, QT included. |
|---|---|
| Mac | QuickTime Player opens formats Apple supports; VLC or IINA open the rest. |
| iPhone and iPad | The Files app plays formats Apple supports. For others, a player such as VLC for iOS, or converting the file here, is the easiest route. |
| Android | Most gallery and music apps play the common formats; VLC for Android plays almost everything. |
| Web browser | QT plays in Safari when the video inside is H.264; other browsers usually download it. |
Want the technical details? See what a .qt file is, with its MIME type, file signature and a viewer.
QT compared with other video formats
How QT stacks up against the formats people most often convert it to or from:
| Format | Compression | Usually contains | Released | Best for |
|---|---|---|---|---|
| QT | Lossy | H.264, MPEG-4, Sorenson or other QuickTime codecs with AAC or other audio | 1991 | QuickTime movies from older Macs, CD-ROMs and early web video |
| MP4 | Lossy | H.264 or H.265 video with AAC audio | 2001 | phone videos, YouTube uploads, social media and streaming |
| MKV | Lossy | almost any codec, often H.264 or H.265 with several audio and subtitle tracks | 2002 | films and TV rips, OBS recordings and anime releases |
| WebM | Lossy | VP8, VP9 or AV1 video with Vorbis or Opus audio | 2010 | web video, screen recorders and browser-based recordings |
| AVI | Lossy | MPEG-4 Part 2 (Xvid, DivX), MJPEG or uncompressed video with MP3 or PCM audio | 1992 | older camcorders, digital cameras and legacy video libraries |
How to use the QT converter
- Choose the format you want in the Convert to menu.
- Drop your QT files on the box, or press Choose QT files. Several files can go in at once.
- Adjust the settings if you need to; the defaults suit most people.
- Press Convert and save each file with its Download button. Nothing is uploaded at any point.
Tips for converting QT files without losing quality
QT is lossy, so some detail was already discarded when the file was made. Converting it cannot bring that back. Converting to a lossless format preserves what is left exactly but makes the file larger; converting to another lossy format adds a small extra loss, which is invisible at sensible settings.
- Keep the original recording. Every re-encode costs a little detail, so convert from the best copy you have, not from a file that was already converted.
- Know whether you need a new container or a new codec. MOV, MKV and MP4 can all hold H.264 video, and switching between them is fast and lossless; changing the codec means re-encoding, which is slower.
- For sharing, MP4 with H.264 at 1080p or 720p is the safe choice: every phone, browser and social network plays it.
- Phones record at very high bitrates. If a file is too big to send, lowering the resolution to 720p usually shrinks it far more than any quality setting.
Convert QT files from the command line
Everything this page does can also be done in a terminal. The most common QT conversion, to GIF, looks like this with ffmpeg:
ffmpeg -i input.qt -vf "fps=12,scale=480:-2:flags=lanczos,split[a][b];[a]palettegen[p];[b][p]paletteuse" -loop 0 output.gifChange the output extension to pick another format. The converter above runs the same ffmpeg engine inside your browser, so you get the result without installing anything.
QT converter FAQ
What is a QT file?
QT stands for QuickTime movie, an alternative extension for a video format created by Apple in 1991. QT is the original extension of QuickTime movies, from the days when Mac files had no extensions and Windows needed one. A QT file is the same container as a MOV, so renaming it to .mov is often all a program needs.
How do I open a QT file?
QT plays in Safari when the video inside is H.264; other browsers usually download it. If the program you need will not open it, convert it to a more widely supported format above.
What is the most common QT conversion?
QT to GIF is the conversion people search for most. Sound is dropped, because GIF cannot carry audio.
Does converting QT files here upload them?
No. Every conversion on this page runs inside your browser, so your QT files never leave your device.
Is the QT converter free?
Yes. There is no sign-up and no watermark, and no limit on how many QT files you convert. The site is supported by advertising.
Can I convert QT files on iPhone or Android?
Yes. Open this page in Safari on iPhone and iPad, or in Chrome on Android, choose your QT files and download the results to your Downloads folder.
Can I convert several QT files at once?
Yes. Drop as many as you like; they are converted one after another, each with its own download button.