Beta
Lot size calculator that accounts for spread and commission.
Lot size calculator for forex daytrader and scalpers accounting in spreads and commissions
A Chrome Sidepanel for tight-stop forex daytraders wondering why they risk more than planned.
Get in early - more than 40 traders are using dynapips daily | 4.3 ★
You are risking more than 1% per trade
Other lot size calculators don't include commission and spread in their calculations. dynapips does.
1% risk should mean 1% risk.
Risk 1% of a $50k account and spread plus commission can quietly turn that into 1.3% or more, before the trade has even moved against you.
How the calculation accounts for spread and commission
dynapips works backward from your risk amount. It takes your stop-loss distance, adds the spread, subtracts what the broker's commission will cost at that size, and solves for the lot size where the total loss — if you're stopped out — matches the percentage you meant to risk.
- 1
Risk amount
Account balance multiplied by the percentage you're willing to risk on the trade.
- 2
Effective stop distance
Stop-loss distance plus the current spread, measured in pips.
- 3
Commission cost
What the broker charges on a round turn at the lot size being tested.
- 4
Lot size
Solved so the stop distance and commission together equal your risk amount — not the stop distance alone.
Coming next
Capture the trade while context still exists.
When the trading journal ships, capturing screenshots, notes, and setup context will happen without leaving the chart — so review is built on evidence, not memory.
Frequently asked questions
What's available right now?
The lot size calculator is live today in the Chrome extension, free to use. The trading journal is in development — joining the waitlist gets you access as soon as it ships.
How is this different from other lot size calculators?
Most lot size calculators size a position from balance, entry, and stop-loss alone. dynapips also accounts for spread and commission, so the lot size it gives you matches the risk percentage you actually intended, not just the risk before costs.
Who is dynapips built for?
Intraday traders and scalpers trading $50k or more in capital, where spread and commission are large enough relative to the stop to meaningfully change the real risk on a trade.
Is dynapips a signal service?
No. Dynapips does not provide trade signals, entries, or investment advice. It is workflow software for traders running their own system.
Is dynapips free to use?
The lot size calculator is free. Pricing for the full trading journal will be shared with the waitlist before it leaves early access. You can pre-order it with a 50% discount.
Does dynapips work with my broker or trading platform?
dynapips runs as a Chrome side panel, so it sits alongside whatever charting and broker platform you're already using in the browser — no separate install or account link required.