What are my trading costs really costing me?

Annual trading fees and commission drag as a % of your portfolio, and their 10-year damage.

Portfolio value ($)

Trades per month

Commission per trade ($)

Assumed annual return (%)

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Annual trading cost ($)

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Annual cost as % of portfolio

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10-year cost if invested

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Cost per trade ($)

How are annual costs computed?

Annual = trades/mo × 12 × commission. Drag % = annual ÷ portfolio. With $25k, 4 trades × $2.50 = $120/yr = 0.48% — before you even earn a %.

Why does 10-year cost use the return rate?

Every dollar paid to your broker stops compounding. The $1,200 of 10 years of fees at 7% grows to roughly $1,700 in lost wealth — the tool shows that gap.

What about the bid-ask spread?

Spread is a hidden cost on top of commissions. If your asset trades a 0.1% spread, add ~0.1% of trade value as an extra commission to see the true drag.