Trading Expectancy Calculator: Expectancy in R and Money

How to calculate trading expectancy

Expectancy weights each outcome by how often it happens and how large it is. The formula is:

Expectancy (R) = (Win rate x Average win) - (Loss rate x Average loss)

Win rate and loss rate are decimals that sum to 1 (a 45% win rate is 0.45, so the loss rate is 0.55). Average win and average loss are stated in R, where 1R is the amount risked per trade. Multiplying the result by the money value of 1R converts expectancy into a dollar figure, and multiplying by trades per month scales it into a monthly number. This tool runs the exact same arithmetic; see lib/tools/expectancy.ts for the two entry points, calculateExpectancy for summary stats and expectancyFromTrades for a raw trade list.

A worked example

A strategy wins 40% of trades. The average win is 3R, the average loss 1R, at 20 trades a month and $50 risked per trade:

Expectancy = (0.40 × 3) − (0.60 × 1) = 1.2 − 0.6 = 0.6R, or $30 per trade
Monthly expectancy = 0.6R × 20 = 12R, or $600
100-trade projection = 0.6R × 100 = 60R, or $3,000, before costs and before the variance that a real 100-trade run will actually show

The 100-trade projection, and why win rate alone misleads

A 40% win rate reads as a losing record to most people, because most people compare it to a coin flip. It is not a losing record here: the winners are three times the losers, so the strategy nets a positive 0.6R every trade on average. Flip the shape and a strategy that wins 70% of the time, with small wins and a large occasional loss, can carry negative expectancy even though the win rate looks strong on a scoreboard.

The 100-trade projection exists to make that concrete: it is the expectancy per trade scaled up, not a forecast of what the next 100 trades will actually return. Real trade sequences are lumpy, a handful of outsized wins or losses can dominate a small sample, and a strategy needs a large enough sample before its realized results resemble its expectancy. Treat the projection as what the edge is worth on average, over a long enough run to let averages hold, not as a schedule.

When it misleads you

Expectancy is only as good as the win rate and R multiples you feed it, and both usually come from a small, self-reported sample. It also ignores costs: spread, commission and slippage all subtract from the reward side and matter most on tight stops, so a marginal 0.1R edge can vanish once real costs apply. And expectancy says nothing about the sequence of wins and losses, which is what actually determines whether you can survive to see the long-run average, a question position sizing answers, not this tool.

How to use this tool

Choose parameters or trade list. Parameters mode takes a summary win rate and average win/loss in R. Trade list mode takes individual trade results in R and derives those averages for you.
Enter win rate, average win and average loss. In parameters mode, a win rate as a percent and the average win and average loss, each expressed as a multiple of the risk taken (R).
Or list your trade results. In trade list mode, add each trade’s result in R: a positive number for a win, negative for a loss.
Set trades per month and risk per trade. Trades per month scales expectancy into a monthly figure; risk per trade converts R into money.
Read expectancy and the 100-trade projection. The tool shows expectancy per trade and per month, in R and in money, plus what that expectancy adds up to over 100 trades.

Frequently asked questions

What is a trading expectancy calculator?

A trading expectancy calculator turns your win rate and average win and loss, both expressed in R multiples, into a single number: the average result of one trade. Enter the three inputs and it applies the standard formula, expectancy equals win rate times average win minus loss rate times average loss, to show expectancy per trade, per month, and projected across 100 trades.

What is the trading expectancy formula?

Expectancy = (win rate x average win) minus (loss rate x average loss), with win and loss rates as decimals and average win and loss stated in R multiples, where 1R is the amount risked on a trade. The result is the expected gain or loss per trade in R, which this tool also converts to money once you enter what one R is worth.

Why does this tool have a trade list mode?

Because summarizing your own results into a single win rate and average win and loss is error prone. The trade list mode takes the raw R multiple of each trade, positive for a win and negative for a loss, and derives the win rate and averages for you, so the expectancy comes from your actual numbers rather than a rounded estimate.

Can expectancy be positive with a losing win rate?

Yes. A strategy that wins 35 to 40 percent of trades can still carry a strongly positive expectancy if the average win is several times the average loss, because expectancy weights the size of the outcome as well as its frequency. The reverse is also true: a 70 percent win rate can be negative expectancy if losses run large. See the r multiple field and try both directions to see this for yourself.

Is this expectancy calculator free?

Yes. It runs entirely in your browser, there is no signup, and nothing you type is sent to a server. The numbers come from the formula on this page, in both parameter and trade-list mode, so you can check them by hand.

Related tools and guides

Trading expectancy explained: the formula, the full worked example, and why it beats win rate as a measure of edge.
Risk/reward calculator: the ratio and breakeven win rate for a single planned trade, without the trade-history math.
Trade setup grader: scores a single setup against fixed rules before you take it.
Win rate vs risk/reward: how the two trade off against each other and why neither alone tells the full story.

Educational only. Not financial advice. NFA. Bullynx is not a registered investment adviser or broker-dealer. Trading and investing involve significant risk of loss. Read the full risk disclosure.