Learn

The ideas behind the tools

Short, plain explainers, each with a live page to try it on.

What is a reverse DCF?A reverse DCF works backwards from today's price to the growth the market is assuming. It turns "what is this worth?" into an easier question: is that growth believable?How to read a 13F filingEvery quarter, large investment managers file a 13F listing their US stock holdings. Here is what the filing shows, what it hides, and how to use it without fooling yourself.What insider buying tells youWhen executives and directors buy their own company's stock with their own money, it is public within two business days. Here is how to tell a meaningful purchase from noise.What is free cash flow?Free cash flow is the cash a business produces after paying to maintain and grow itself. It is harder to dress up than earnings, which is why valuation models start from it.