The derivation explorer
Enter the quantities you have and the one you want. No account is needed — the search, the graph, the algebra and your own dropped-in formulas all work signed out.
What you can do here
Solve for a target from known values and read the derivation step by step. Browse all 65 formulas and calculate any of them directly. See the relationship graph and follow which formula feeds which. Express a quantity symbolically in terms of the variables you choose, rendered as real mathematics. Plot any formula over a range of one of its inputs.
Your own equations
A formula pack is a small JSON file of your own relations. Drop one in and it joins the graph for as long as the page is open — no account, no upload, no waiting. The format is documented on the packs page, and the file never leaves your browser except as the body of the search you asked for.