The short answer
Yes, and no. There are free tools that will convert a 2D video to 3D. What they ask for instead of money is a computer that can handle it, an afternoon of your time, and a willingness to learn what a depth map is. If that sounds fine, they are a real option.
What we do differently is take that work off your hands. Your first 2 minutes are free here, without a credit card, so you can see the result on your own headset before deciding whether it is worth paying for.
What free desktop software actually costs you
The free tools run on your own machine. That means the conversion is as fast as your graphics card, and a long video can occupy your computer for hours. You also do the setup: installing, choosing settings, and working out why the first attempt looked wrong.
Many people enjoy that. If you are not one of them, the honest trade is that you are paying with time rather than with money.
What you get for free here
Two minutes of conversion, one free trial per email address, and no card details. That is enough to convert a short clip and watch it properly in your headset, which is the only way to judge whether the depth looks right to you.
The result streams straight to the browser in your headset, so there is nothing to install and nothing to copy across.
How to judge the result
Watch it in the headset, not on your laptop. On a flat screen a 3D file tells you almost nothing. In the headset you are looking for one thing: does the depth feel natural, or does it make your eyes work too hard?
If it feels too strong or too flat, that is usually the depth setting rather than the video. There are three profiles to choose from, and the same footage can look quite different between them.
Which videos convert well
Footage with a clear foreground and background converts best: someone standing in a room, a landscape with something close to the camera. Flat, evenly lit scenes have less for the depth estimation to work with, so the effect is subtler.
That is worth knowing before you spend your free minutes. Pick a clip where something is obviously nearer than the rest.