Working out position size
We use EUR/USD around 1.0850 and a naira figure throughout, because the cost of being wrong is the only number that decides whether the account survives.
Where the pip value in naira actually comes from
A pip on EUR/USD is a move in the fourth decimal place, so a rise from 1.0850 to 1.0851 is one pip. On a standard lot of 100,000 units, that pip is worth 10 United States dollars. The naira figure comes from converting those dollars at whatever exchange rate your broker applies at the time.
That is why the pip value moves. If the rate is ₦1,540 to the dollar, 10 dollars is ₦15,400. If the rate later becomes ₦1,600, the same pip on the same lot is ₦16,000. The instrument has not changed and the lot has not changed, but the naira cost of the same mistake has.
Brokers differ in the rate they use and in when they apply it. Some publish a fixed conversion for the day, some use a live rate, and some quote the account in dollars and convert only when money enters or leaves. Read the contract specification your broker publishes rather than assuming the figure you saw yesterday still holds.
What the minimum trade size does to your stop
Position sizes are not continuous. A broker allows 0.01 lots, then 0.02, then 0.03, and nothing in between. When the calculation gives 0.026, the reachable sizes are 0.02 and 0.03. Rounding up to 0.03 risks more than the amount you set out to lose, so the safe direction is down.
Rounding down has a cost of its own. At 0.02 lots your risk per pip is ₦308, and a 30 pip stop loses ₦9,240 rather than the ₦12,000 you were prepared to lose. You are not fully using the risk you allowed, and that is the point. The unused ₦2,760 is the price of staying inside the rule.
The harder case is when the smallest size is already too large. At 0.01 lots the risk per pip is ₦154, so a 100 pip stop loses ₦15,400. If your risk amount is ₦9,000, no allowed size makes that stop affordable. The choice is a tighter stop, a smaller risk amount, or no trade. There is no fourth option that keeps the stop and the risk amount together.
Why the stop distance is decided before the size
The stop distance comes from the chart, not from the size you would prefer. It is the distance at which the reason for the trade no longer holds. If that distance is 45 pips, then 45 pips is the number that goes into the calculation, and the size is whatever falls out of it.
Choosing the size first reverses this. A trader who wants 0.10 lots and a ₦12,000 risk needs a stop of 7.8 pips at ₦1,540 per pip. A stop that tight sits inside the ordinary movement of EUR/USD and is likely to be hit before the trade has room to work. The size has quietly rewritten the plan.
The calculation also tells you when not to trade. If the honest stop distance gives a size below the broker minimum, the trade is too expensive for the account at that moment. Skipping it costs nothing. Taking it at the wrong size turns a planned loss into an unplanned one, and the account pays for the difference.
A ₦20,000 risk with a 25 pip stop
| Step | Amount | Note |
|---|---|---|
| Money at risk | ₦20,000 | This is the amount you have decided you can lose on this one trade. It is not the size of your account. |
| Stop distance | 25 pips | The distance from your entry price to your stop loss, measured in pips. On EUR/USD, one pip is 0.0001. |
| Value of one pip on one standard lot | 10 units of the quote currency | One standard lot is 100,000 units. 100,000 multiplied by 0.0001 equals 10. The quote currency is USD, so this is 10 USD per pip before conversion. |
| Pip value in naira | ₦15,400 | 10 USD converted at an assumed rate of ₦1,540 to the dollar. The rate your broker uses will differ and will change. |
| Risk divided by stop distance | ₦800 per pip | ₦20,000 divided by 25 pips equals ₦800 for each pip the price moves against you. |
| Position size | 0.05 lots | ₦800 divided by ₦15,400 per pip per standard lot equals 0.052. Rounded down to 0.05 lots. |
Brokers round position sizes to the nearest allowed step, and many add a spread, commission or swap on top. The pip value in naira also moves with the exchange rate. Check the contract specification your broker publishes, because the exact pip value and the minimum trade size vary between brokers.
Doing it once, step by step
You will work through one position size from three numbers, in the order the lesson gives. Do the division first, then apply the broker's step, then check the result against your risk amount.
- 01
Write down the risk amount in naira
Decide the money you are willing to lose on this trade and write it as a naira figure. Use a number the account can absorb without changing how you trade the next day. For this walkthrough the figure is ₦12,000.
- 02
Measure the stop distance in pips
Find the price at which the trade idea is wrong and count the pips from entry to that price. Use the chart, not a round number that feels comfortable. Here the distance is 30 pips.
- 03
Divide the risk amount by the stop distance
₦12,000 divided by 30 pips gives ₦400 per pip. This is the risk per pip your position may carry. It is an intermediate figure, not the answer.
- 04
Divide by the pip value of one standard lot
One pip on a standard lot is ₦15,400 at the rate used here. ₦400 divided by ₦15,400 gives 0.026 lots. This is the size before the broker's step is applied.
- 05
Round down to the broker's allowed step
Brokers allow sizes in fixed steps, commonly 0.01 lots, and the exact step varies between brokers. Round 0.026 down to 0.02 lots. Rounding up would risk more than ₦12,000.
- 06
Check the rounded size against your risk amount
At 0.02 lots one pip is worth ₦308, so a 30 pip stop loses ₦9,240. That is inside the ₦12,000 limit. If the rounded size had produced a loss above the limit, the trade would be skipped or the risk amount reduced.
The mistake most people make here
The common mistake is to pick a lot size first because it feels familiar, then place the stop wherever the chart allows. That reverses the calculation. If the stop is wider than the size can support, the loss in naira is larger than the amount you planned to risk, and one trade can remove several weeks of progress. Work out the position size last, from the stop distance, and if the answer is smaller than your broker's minimum trade size, the honest response is to skip the trade or accept a smaller risk amount. The size is an output, not a starting point.Check yourself
You will risk ₦12,000 with a stop 30 pips away. One pip on a standard lot is worth ₦15,400. What position size does that give?
₦12,000 divided by 30 pips equals ₦400 per pip. ₦400 divided by ₦15,400 per pip per standard lot equals 0.026. Rounded down to the nearest allowed step, that is about 0.02 lots.
You are risking ₦9,000 and your broker's smallest position is 0.01 lots. One pip on a standard lot is ₦15,400, so one pip on 0.01 lots is ₦154. How many pips can your stop be?
₦9,000 divided by ₦154 per pip equals about 58 pips. A stop wider than that would risk more than ₦9,000 at the smallest size available.
Your risk is ₦20,000 and the stop is 25 pips. What is the risk per pip in naira?
₦20,000 divided by 25 pips equals ₦800 per pip.
Questions that come up next
How do I find the pip value in naira for the pair I am trading?
The pip value on a standard lot is 10 United States dollars for any pair where the dollar is the quote currency, such as EUR/USD. Your broker converts that figure into naira at a rate it sets. The rate varies between brokers and can change during the day. Check the contract specification your broker publishes for the exact figure. Do not carry yesterday's naira pip value into today's calculation without checking it again.
What if my broker only allows 0.01 lots and my stop needs a smaller size?
Then no allowed size makes that stop affordable at your chosen risk amount. You have three honest options. Tighten the stop to a distance the smallest size can support. Reduce the amount you are willing to lose. Or skip the trade. Keeping both the wide stop and the full risk amount is not one of the options, because the arithmetic does not allow it.
Does the spread change the position size I calculated?
The spread changes the price you enter at, so it can change where your stop sits in pips. Many brokers also charge commission or swap on top of the spread. Your calculation uses the stop distance in pips, so if the spread pushes your effective entry further from the stop, the distance grows and the size must shrink. Build the spread into the stop distance before you divide.
Why not round 0.026 lots up to 0.03?
Rounding up increases the money at risk beyond the amount you set. At 0.03 lots your risk per pip is higher than at 0.02, so the same 30 pip stop loses more naira than you planned. The safe direction is always down. Rounding down means you risk less than allowed, and the unused amount is the cost of staying inside your rule.
How often should I recalculate the pip value in naira?
Recalculate it whenever the exchange rate your broker uses changes, and check it before each trade if your broker uses a live rate. A pip value that was ₦15,400 at one rate becomes ₦16,000 at a higher rate, with no change to the instrument or the lot. The naira cost of the same mistake moves with the rate. Treat the pip value as a number to look up, not a number to remember.
Can I use this calculation for any instrument, not just EUR/USD?
Yes, the order is the same: risk in money, divided by stop distance in pips, divided by pip value. What changes is the pip value, which depends on the instrument, the lot size and the conversion rate your broker applies. Some instruments quote in different decimal places, so confirm what counts as one pip on that instrument. The contract specification your broker publishes will say.
The words used on this page
- Pip
- The smallest standard move in a currency pair's price, usually the fourth decimal place. On EUR/USD, a rise from 1.0850 to 1.0851 is one pip. The naira value of one pip depends on the lot size and the exchange rate your broker uses.
- Lot
- A standard unit of trade size. A standard lot is 100,000 units of the base currency. Brokers also allow smaller sizes such as 0.01 lots, called a micro lot, but only in fixed steps.
- Stop distance
- The number of pips between your entry price and your stop loss order. It comes from the chart, at the point where the reason for the trade no longer holds. It is the second number in the position size calculation.
- Risk amount
- The money in naira you are willing to lose on a single trade if the stop is hit. It is the first number in the calculation. It is a decision you make before you look at the chart, not a number that falls out of the size.
- Contract specification
- The document your broker publishes that lists the pip value, the minimum trade size, the spread, commission and swap for each instrument. The exact figures vary between brokers. Read it rather than assuming.
- Rounding down
- Reducing the calculated position size to the nearest allowed step below it. If the calculation gives 0.026 lots, rounding down gives 0.02. This risks less than your full risk amount, which is safer than rounding up.
What to take away
- Position size is an output: risk in money, divided by stop distance in pips, divided by pip value, in that order.
- The pip value in naira moves with the exchange rate and varies between brokers, so check it before each trade.
- Round the size down to the nearest allowed step, never up, and if the smallest size is still too large, skip the trade or reduce the risk amount.
- The stop distance comes from the chart first; the size is whatever the arithmetic allows after that.