The Trade Cost Workbook

Count what a stock trade really costs: the round trip, the price that breaks even, a position size whose loss stays inside your limit with costs included, and a journal that measures the rest

StockTrick's free calculators each answer one question on clean prices. The Position Size Calculator sizes a trade from the distance to the stop, the Risk/Reward Calculator compares distances before costs, and the Stock Profit Calculator nets a fee but never says where the trade breaks even. A real order pays a commission, crosses the bid-ask spread and often fills a little worse than the quote. While writing this pack we tested our own calculators at their edges and fixed them: the position size tool rounded the risk per share before dividing (10,000 shares where 7,142 was the limit), sized a stop on the wrong side of the entry, and sized positions bigger than the account. The Trade Cost Workbook carries the costs through all three questions. In the worked example, 91 shares at $50 with a $5 commission an order, a 4-cent spread and 2 cents of slippage a side cost $17.28 in and out and break even at $50.19; the calculator's 100 shares on a $200 limit lose $218.00 once costs are paid, while 91 shares stay inside it at $199.28; a 3 : 1 trade needing a 25% win rate on paper is 2.65 : 1 needing 27.4% after costs; and twenty round trips a month cost $4,147.20 a year. Seven steps cover the round trip, the break-even, sizing with the costs inside the loss, a price that opens past the stop, the ratio after costs, the yearly bill and a trade journal. This is neutral arithmetic and record-keeping, not investment advice: trading can lose money, including more than you expect, and the calculator does not know your situation. It names no security and suggests no trade, strategy or risk percent; the worked numbers are examples, and the example journal loses money after costs. Long trades in shares only; taxes and per-trade charges are left to your local rules. Included: 24 printable pages with a cost card, a pre-trade sheet, a trade journal, a monthly review, reference tables and a quickstart, plus a personalised sheet worked from the numbers you enter in the Stock Profit, Position Size and Risk/Reward calculators.

Look inside

Two full pages from the workbook, exactly as printed. Click either to read it at full size before you decide.

What is in it

• The Both Sides Rule: the round trip, itemised: commissions, spread, slippage and percent charges on both sides
• The Break-Even Rule: the exit price that nets zero, rounded up to the cent, by share count and commission
• The Costs Inside Rule: a position size whose loss at the stop stays inside your limit with costs included, capped by the cash
• The Gap Rule: the loss if the price opens past your stop, as a share of your limit
• The Net Ratio Rule: the reward-to-risk ratio and the win rate it needs after costs, and why tight stops weigh the costs most
• The Frequency Rule: what your round trips cost in a year, in dollars and as a share of the account
• The Written First Rule: a journal written before the order and finished after it, which measures your real slippage
• Four working pages: a cost card, a pre-trade sheet, a trade journal and a monthly review
• Reference tables of the move needed to break even by price and share count and the win rate needed by ratio and cost share, and a quickstart
• A personalised sheet worked from the figures you enter in the Stock Profit, Position Size and Risk/Reward calculators

The workbook picks up where the free Position Size Calculator leaves off. The calculator sizes a trade from the distance to the stop; the workbook puts the commissions, the spread and slippage inside that loss, finds the price that breaks even, nets the risk/reward ratio after costs, and adds a trade journal that measures your real costs. It is neutral arithmetic and record-keeping for long trades in shares: no picks, signals or strategies. It is not investment advice. Trading can lose money, including more than you expect, and the calculator does not know your situation.