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Surprised Your P&L Calculator's ROI Looks Low?

The calculator isn't wrong — it's measuring a different baseline. Here's how to read ROI correctly.

Surprised Your P&L Calculator's ROI Looks Low?
Photo by Towfiqu barbhuiya on Unsplash

If the Number Caught You Off Guard

You've probably seen someone in a leverage trading community claim '50% on this trade' — then you plug the exact same entry and exit into a P&L calculator and get an ROI closer to 5%. The calculator isn't broken; the two numbers are just measuring return against different bases.

Miss that distinction and you'll either assume the calculator is wrong, or take an advertised return at face value and underestimate the actual risk you're taking.

What This Calculator's ROI Is Actually Measured Against

Net profit is gross profit — (exit price - entry price) × quantity — minus fees. ROI is that net profit divided by the total position size (entry price × quantity), not your margin.

Entry $100, exit $105 (a 5% price move), quantity 10 (a $1,000 position), 0.05% fee, long: gross profit = 5 × 10 = $50, fees = (100+105) × 10 × 0.05% ≈ $1.03, net profit = 50 - 1.03 ≈ $48.98. The calculator's ROI is 48.98 ÷ 1,000 × 100 ≈ 4.90%.

If You Used Leverage, Your Felt Return Is Different

If that same position used 10x leverage and your actual margin was $100, your return on margin is 48.98 ÷ 100 × 100 ≈ 48.98%. The ROI the calculator shows (4.90%) is against the full position size; the 'leveraged return' traders usually quote is against the margin you actually put up — two different numbers.

Neither one is wrong — they just measure different things. But if you don't know which basis you're looking at, the gap between your felt return and the calculator's ROI gets more confusing the more leverage you use.

Why Fees Cut Deeper Than You'd Expect

This calculator applies fees at both entry and exit — one charge to open the position, one to close it, both subtracted from net profit.

A 0.05% rate looks small, but as leverage scales up your position size (quantity × price), the absolute fee amount scales up right along with it. Bigger leverage means bigger profits, but the fee burden grows at the same rate.

Styles that open and close positions frequently in short cycles (scalping) feel this cost accumulate fastest, since it hits the overall return every single round trip.

Check the exact net profit and ROI, fees included, with the calculator.

Go to the Calculator →

Where This Leaves You

Before opening a position, run the expected net profit and ROI through a P&L calculator so you know in advance how much price movement you actually need before fees stop eating your gain.

If you're using leverage, get in the habit of distinguishing the calculator's ROI (against full position size) from your actual return on margin. Knowing both numbers is what lets you gauge your real risk accurately.

Use SizerTrade's P&L Calculator

Ready to Put This Into Practice?

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Compare Exchange Fees at a Glance

MakerTaker
Binance0.020%0.050%
Bybit0.020%0.055%
Bitget0.020%0.060%
OKX0.020%0.050%

Official regular-tier fees as of 2026-07-22. Rates vary by tier and promotions — click an exchange name for the latest figures.