Free investing tools.
Quick calculators for the math that actually comes up. No signup, nothing stored — everything runs in your browser.
Position size calculator
Work out exactly how many shares to buy for a trade based on your account size and how much you're willing to risk.
Open tool →Capital gains & loss calculator
Estimate the tax on a sale, and see how a losing position could offset your gains.
Open tool →Cost basis calculator (FIFO / LIFO)
Bought the same stock at different prices? See your cost basis and realized gain under each accounting method.
Open tool →