Stock Profit Calculator

What this tool is used for

• Working out the actual return on a trade after broker fees.
• Finding the break-even price for a position.
• Working out what a position must reach to cover a dividend-adjusted cost basis.
• Checking a realised gain against a broker's statement.
• Seeing how a per-trade commission changes the maths on a small position.

Frequently Asked Questions

What is included in the return?

The difference between sale proceeds and purchase cost, less the commissions you enter. It excludes dividends, so for a long-held position the figure understates your actual return — total return is price change plus income, and for some shares income is most of it.

Why does the break-even price sit above what I paid?

Because commission is paid twice — once buying, once selling — and the sale side is charged on the larger amount. The price has to rise enough to cover both before a single unit of profit exists.

How is percentage return calculated?

Profit divided by the total amount invested, including the buying commission. Dividing by the sale proceeds instead gives a smaller and flattering number, and the two get quoted interchangeably far more often than they should be.

Can I compare this with an annual return?

Not directly. A 20% gain over three months and a 20% gain over three years are wildly different; annualising the first gives roughly 107%, the second about 6.3%. Use a CAGR calculation whenever the holding periods differ.

What about tax?

Not included, and it can be the largest single deduction. Rates commonly differ between short- and long-term holdings, losses may offset gains, and rules vary by country. This is a gross figure — and none of it is financial advice.

What does the return figure leave out?

Time and tax. A 20% gain over five years is not comparable to 20% in one, and the after-tax figure depends on your holding period and jurisdiction — so this is a gross trade result, not a personal outcome.

Common errors and gotchas

• Omitting fees on both legs, which on small positions can exceed the gain.
• Ignoring the spread, which is a cost even when commission is zero.
• Forgetting tax, which applies to each disposal in most jurisdictions.
• Comparing a percentage return without the holding period.
• Treating an unrealised figure as a gain before the position closes.