The calculator starts from the closing price on your start date and buys as many shares as the amount allows, fractions included. If the market was shut that day, it uses the next session’s close. Returns with dividends reinvested are computed from the adjusted closing price, which already reflects every dividend paid back into the holding, so later dividends are earned on a slightly larger position. Splits are reflected in the same series, so a 4 for 1 split does not show up as a fall. Share counts are shown on a split-adjusted basis so the starting and ending figures remain comparable.
Price return only is the same purchase held without reinvesting anything, which is why the two lines in the breakdown differ. The annualized figure is a compound annual growth rate: the single yearly rate that turns the amount invested into the ending value over the same span. It is left out for periods under a year, where a yearly rate says nothing useful.
Fees, spreads, currency conversion and taxes are not modeled. Amounts are stated in the security’s own trading currency, so a Paris listing is calculated and labeled in euros.
Does this include dividends?
Yes, and it is on by default. With reinvestment on, each dividend buys more shares at the price on the day it was paid. Turning it off leaves the dividends uninvested, so only the share price drives the result. The breakdown shows both figures either way, so you can see how much of the gain came from dividends.
Why is the total return different from the price chart?
A price chart shows what one share cost. This shows what a holding was worth, including the shares that dividends bought along the way. For a high yielding stock held over decades, the gap between the two can be larger than the price gain itself.
What happens if I pick a date before the stock was listed?
The Custom period opens a start and end date. If the start falls before the listing, it moves forward to the first trading day on record and a note appears beside the dates naming that day. The calculation then runs from there.
Are splits handled?
Yes. The price history is split adjusted, so share counts and prices stay consistent across a split and no artificial drop appears in the chart.
Can I compare against an index?
Pick one in the Compare to control. The second line is drawn from the same starting amount over the same dates, so the two are directly comparable, and the card beside the breakdown says which came out ahead.