Average Cost & Break-Even Calculator
Find your real cost basis after buying in pieces. Enter each lot's shares and price to get your blended average cost — the break-even price the whole position needs to reach.
Your lots
Add each buy (or average-down) lot. Blank rows are ignored. The average cost is your break-even — the price the combined position needs to reach to be flat.
Average cost / break-even
How it works
When you buy a stock in more than one lot — or average down after a drop — your break-even isn't your first price; it's the share-weighted average of every lot. Average cost = total dollars spent ÷ total shares. That blended number is the price at which the combined position is flat.
Averaging down lowers your break-even but also adds risk: you're committing more capital to a position that's already moving against you. It works when your thesis is intact and you've planned the adds in advance; it hurts when it's a reflex to a losing trade with no stop. Size the adds, and know the level that would prove you wrong.
StockSetups attaches a stop and target to every setup, so you can decide ahead of time whether a name is worth adding to — or whether the stop says it's time to step aside.
Frequently asked
How do you calculate average cost?
Average cost = total amount spent ÷ total shares owned. Multiply each lot's shares by its price, add those up, and divide by the total shares. The result is your blended cost basis and break-even price.
What is averaging down?
Buying more of a stock at a lower price than your initial entry, which lowers your average cost. It reduces your break-even but increases the capital and risk committed to a losing position — best done with a plan and a stop, not as a reflex.
Is my break-even the same as my average cost?
Yes — ignoring commissions and fees, your break-even price equals your average cost. Reach that price and the position is flat.
Let the scan do the math.
StockSetups draws the levels and works out the entry, stop, target and R:R on every setup it finds — free for 7 days.
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