Tutorial: Build a JavaScript Tool to Calculate Crypto Trade Risk Before Ordering

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A developer on DEV Community has published a tutorial on building a plain JavaScript crypto position-risk calculator, inspired by a personal $100 loss on a leveraged trade that lacked a stop-loss. The tool combines position quantity, entry price, stop price, trading fees, and a slippage buffer to estimate total dollar risk before an order is placed. Unlike leverage, which only determines the margin required, the actual dollar loss depends on the quantity of tokens and the price distance to the stop. The tutorial walks through a sample calculation where 1,500 tokens entered at $0.620 with a stop at $0.608 produce an $18 price loss, rising further once fees and slippage are added. The function also includes validation logic to catch a common error where a stop is placed on the wrong side of the entry price.

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