Cost Basis Calculator: New Purchase

Your new average cost per share after buying more of a stock, plus total invested and the gain or loss at the current price, worked instantly as you type.

Shares held

Cost basis per share ($)

New shares to buy

Purchase price per share ($)

Current market price ($)

Calculating…

New blended cost basis vs. the number of new shares purchased. The dashed line is your current basis; the marker shows your purchase.

Assumption check

For averaging into a stock you already hold. Enter the shares you are buying, not the dollars.

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