The formula in three steps
First, place the stop where the trade thesis is no longer valid. Second, convert that distance into ticks. Third, divide the maximum dollar risk by the risk of one contract. Put fees and a realistic execution allowance in the denominator rather than discovering them after the trade.
MNQ example: a 40-point stop equals 160 ticks because MNQ trades in 0.25-point increments. Each tick is worth $0.50, so one contract carries $80 of stop risk before costs. A $250 risk budget fits three contracts mathematically; an allowance for fees and slippage may reduce that number.
ES, NQ, MES and MNQ do not carry the same dollar risk
Contract count alone tells you almost nothing about risk. CME specifications put one ES tick at $12.50, one NQ tick at $5, one MES tick at $1.25 and one MNQ tick at $0.50. The same chart distance therefore produces a very different dollar outcome across products.
Micro contracts are not automatically safe. They allow finer sizing. Ten Micro E-minis approximate the index exposure of one corresponding E-mini; splitting the position does not make the underlying risk disappear.
| Contract | Tick size | Tick value | Value per index point |
|---|---|---|---|
| ES | 0.25 points | $12.50 | $50 |
| NQ | 0.25 points | $5.00 | $20 |
| MES | 0.25 points | $1.25 | $5 |
| MNQ | 0.25 points | $0.50 | $2 |
The stop determines size—not the other way around
A common sizing mistake happens before the calculator is opened. The trader chooses a desired number of contracts, then pulls the stop closer until the dollar risk appears to fit. That turns position sizing into a justification for a fragile stop.
The stop should sit where the setup is invalid under the chosen method. Only then does the formula determine how many contracts the account can carry. If even one Micro contract exceeds the budget, skipping the trade is a valid result.
Correct orderValidate setup → set invalidation level → measure stop → apply tick value → round contracts down.
Margin is not a loss limit
Intraday margin tells you how much capital a broker requires to open a position. It does not tell you how much that position can lose during an ordinary or exceptional move. Futures are leveraged, so a relatively small price change can create a large change in account equity.
A stop is not a guarantee of the requested exit price either. A fast or thin market can fill worse than planned. A sound sizing calculation therefore keeps room for actual fees and possible slippage in addition to theoretical stop risk.
- Do not use broker margin as maximum trade risk.
- Verify the current tick size and tick value for each product.
- Keep entry and stop on the same contract and price basis.
- Include commissions, exchange fees and execution slippage.
- For prop accounts, also respect daily limits and loss room.
A second example shows why points are not enough
An eight-point stop in MES is 32 ticks. At $1.25 per tick, that is $40 of risk per contract before costs. Four MES contracts therefore carry $160 of theoretical stop risk.
The same eight-point stop in ES is already $400 per contract. The chart distance is identical while the dollar risk is ten times larger. Product, tick value, stop and contract count belong in the same calculation.
Sources and further reading
Contract specifications and margin requirements can change. Verify current exchange and broker data before placing an order. These examples explain the calculation and do not recommend a particular risk level.