Caption Generator

Caption Generator is an online video editor made for making memes. It features a simple to use online interface to add subtitles or captions to any video already uploaded to YouTube. That means you don't have to download any clips and then reupload them again. It's great for traditional "Hitler Reacts" videos, but it doesn't support cutting up clips or adding images to the video. If you'd like to do that, you'll be better off with a more traditional video editor like Windows Movie Maker.

Using Caption Generator
Using Caption Generator is pretty straightforward. The easiest way to start is to pick one of the templates already offered within the video editor—it will already have the timing of the captions laid out for you, so all you have to do is change the text for each one and then publish your video.

If you're interested in making a completely new video, browse YouTube for the clip you'd like to use, making sure it doesn't already have subtitles. Then grab the URL of the video and enter it into the YouTube URL box on Caption Generator. Once you've done that you can start adding and timing new captions.