Latest stable release of VidSync
This version requires OS X 10.9 (Mavericks) or later. It has only been tested in 10.11 (El Capitan) or later, but it should theoretically be compatible with 10.9 and 10.10. It has also been tested with later versions up through 10.15 (Catalina) and is likely to be compatible with versions well beyond that.
Latest version: VidSync 1.661.zip
VidSync used to come in a normal "installer package" you could run to automatically place the program in your Applications folder, but Apple has taken that option off the table for now. So the current version comes as a zip file containing the application. Just unzip and move it into your Applications folder manually.
You can also browse the source code for VidSync on Github, or modify it to create your own version of the program. To modify VidSync in Apple's XCode development environment, go to "Check Out..." under the "Source Control" menu and check out the repository at
Old versions of VidSync
The early 2015 version experiences some latest glitches in OS X 10.11 (El Capitan). They're fixed in the newer version (1.60), which also includes several minor feature improvements and bug fixes.
The installer package should work fine for a fresh install. Sometimes, if you had multiple previous versions of VidSync on your system, it fails to overwrite the correct one, and when you open it from your Applications menu you'll still see the old version. If that happens, download this zipped version and manually unzip it into your Applications folder to make sure you get the new version.
This legacy version is compatible with earlier versions of OS X, from 10.6 (Snow Leopard) and on. It uses the same well-tested mathematical techniques as the current version, but it is less stable and there are several glitches. I highly recommend using a more recent version unless you are using old, 32-bit Mac hardware that cannot run the free upgrade to OS X 10.9 / Mavericks.