Stock profit calculator
Compute floating profit and return, the diluted cost after averaging down, clearing proceeds and the break-even price for A-share positions, with commission, stamp duty and transfer fees applied per current rules.
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Profit result
Diluted cost, floating profit and break-even price.
Enter the buy price and share count to calculate
Cost basis: 0 · Market value: 0 · Floating profit: 0 · Return: 0 · Average cost: 0
What this tool does
- Review a position: enter the buy price, share count and current price to see the floating profit and the real return net of buy fees.
- Before averaging down, enter the add price to see where the average cost lands and whether it is worth it.
- Work out the break-even price before selling, including commission, stamp duty and transfer fees.
- Compare commission tiers — from 0.03% down to 0.015% — to see how much it saves over time.
Example
Input
10,1000
Output
首次买入：10 元 × 1000 股 = 10000.00 元，买入费用 5.10 元 当前价 12 元：市值 12000.00 元 浮动盈亏：1994.90 元（19.94%），平均成本 10.0051 元/股 清仓 @12 元：卖出金额 12000.00 元，卖出费用 11.12 元，净收入 11988.88 元 清仓盈亏：1983.78 元（19.83%） 保本价（含买卖费用）：约 10.0152 元/股 口径：佣金按成交额 × 万分之几（有最低值），卖出加印花税 0.05%，双向收过户费 0.001%；A 股持仓成本采用加权平均法。
Diluted cost uses the weighted-average method: (original cost + added cost) ÷ total shares.
Frequently asked questions
How are the fees computed?
Commission is the traded amount times a rate in basis points with a per-order minimum (default 0.03%, minimum 5 yuan); the transfer fee is 0.001% of the amount charged both ways; stamp duty is 0.05% and only on sells (halved since August 2023). On a 10,000 yuan buy: commission max(3, 5) = 5 yuan plus 0.1 yuan transfer fee gives a 10,005.1 yuan cost basis.
How is the diluted cost computed?
Weighted average: (original amount + added amount) ÷ total shares. Buying 1000 shares at 10 and another 1000 at 8 gives a 18,010.18 yuan cost and a 9.0051 average price — the same method brokers use for position cost.
Why is the break-even price above the average cost?
Because the sell side pays commission, transfer fee and stamp duty again. With 1000 shares at 10 the average cost is 10.0051, but the fee-inclusive break-even is about 10.0152, so you need to clear 10.02 to be genuinely even.
Does averaging down only support equal quantities?
The third input is the add price and the quantity is treated as the same as the first buy, which keeps the dilution maths readable. To model a different quantity, combine both purchases into one pair of numbers (total amount ÷ total shares = average cost).
Why do floating and clearing profit differ?
Floating profit only deducts buy fees, while clearing profit also deducts sell fees (commission, transfer fee and stamp duty), so it is usually lower. Turn off 'include trading fees' to compare gross figures.
Does it fetch live quotes?
No. Every price is entered by you; the tool never goes online and is not investment advice.
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