I looked into this two days ago and decided to get a subscription with https://climeworks.com for a part of my CO2. It's the only thing I can do until the bus that I drive to work with becomes electric, planes for business trip start to fly electrically, there is 100% renewable power, etc. I'm making all the right choices available to me today (such as renewable power at home, recycling, etc.), but even so, many tonnes of CO2 are produced for me every year. I can't just shrug and do nothing.

It's quite expensive, and all of those CO2 sequestration companies (including Climeworks) sound pretty prototype-y. Climeworks is the one with a consumer product and clearly states that they already remove CO2 from the atmosphere today. This is what I got back from sales when I asked if my money will be for R&D that might, one day, remove the CO2, or if it would support operational costs of a machine running today:

> you will receive we state the amount of carbon dioxide that has been removed in your name. No one else can put a claim to that amount. [...] we run the machines most of the time anyway [but] proving that there is a market for our services (such as CDR for individuals) makes it easier for us to broaden the application of our technology.

So that gives me a reasonable confidence, but I'll still spread out my CO2 compensation a little in case part of it turns out to be badly spent. And trees have more advantages than just producing rock, even if we'd need much more surface area and water to maintain those trees than to sequester CO2 into rock.