If you've landed here, it most likely means that the fund checking website didn't work for you. The fund universe covered by the tool will be growing to cover more fund types and new geographic areas. In the meantime, if you work with a broker or financial advisor, the simplest route is to call them up and ask them to find out if your fund is invested in the Carbon Underground 200. He or she can look and see what a fund holds in a couple minutes (literally). If your money is in a 401K retirement plan at your company, call the company that administers the 401k plan. Employers provide contact information to their employees.
By the way, if an advisor says you'll clearly lose out by divesting, ask them to explain why they think that. The more you learn, the more you'll find that the canned negative answers are wrong. See this discussion on some simple reinvestment steps and this discussion on why holding fossil fuel stocks is bad for you your portfolio. There are also many other sources of information on this.
Still don't have an answer? Not to worry. The next thing to do is to simply revisit the broad strategies of any funds you own (scroll down to see how to do that). Many people hold funds that follow a strategy whose basic premise is to hold a lot of stocks across all sectors of the economy, from large companies to small (a "diversified" fund). If that's your fund, its very likely the fund invests in large fossil fuel companies. If, instead, you have money in funds that are focused on small cap stocks, a sector fund (e.g., healthcare), a money market fund or some less diversified fund, the major fossil fuel companies may be outside the group of companies the fund managers can invest in. ("Cap" is shorthand for "capitalization"- the total value of a company's stock.)
If you need to go farther, here's a simple step-by-step process that will help:
(1) Find the "ticker symbol" for the fund. You can locate it on your investment account website, or in printed account statements. Or, if you know the fund name, there are many finance news/information websites that will find the ticker symbol for you. (For example, Google Finance or Yahoo Personal Finance.)
(2) Go to the mutual fund company's website and enter the ticker symbol into the search window. Find the link to the description of your fund. Just reading the overall fund summary is likely to give you the answer. You can also get that information on the financial sites listed above. (Or, just find the mutual fund company's phone number and give them a call.)
(3) There will also be one or more pages that describe the fund's investments ("holdings") in specific companies. If any of those are on the major fossil fuel company list, you have your answer. You might only see a list of the top 10 or 20 largest investments. If the full list isn't there, not to worry. There are more ways to dig a little deeper.
(4) There will also be a summary of all the holdings (sometimes called "fund composition") by industry sector. If there is an "energy" sector category, look to see if the number is greater than 0%.
(5) If you still don't have an answer, here's the next step (for funds sold in US markets):