Pips and Lot Sizes Explained: How to Calculate What a Trade Actually Risks

Two units govern every foreign exchange trade. A pip measures how far the price moved. A lot measures how much you were holding while it moved. Multiply them and you have the number that actually matters: the money at stake.

Getting this arithmetic right is not advanced technique. It is the difference between knowing what you risk and guessing.

What a pip is

A pip is the standard smallest increment in which a currency pair is quoted.

For most pairs it is the fourth decimal place: 0.0001. If EUR/USD moves from 1.0850 to 1.0851, that is one pip.

For pairs quoted against the Japanese yen it is the second decimal place: 0.01. USD/JPY moving from 148.20 to 148.21 is one pip. The difference exists because the yen exchange rate sits on a different scale — using four decimals would produce impractically small increments.

Most brokers now quote an extra digit — the fifth decimal on standard pairs, the third on yen pairs. This is a pipette or fractional pip, worth one tenth of a pip. A price of 1.08505 is 1.0850 and a half pip. It exists because tighter pricing lets brokers compete on spread.

Lot sizes

A lot is a standardised quantity of the base currency.

Lot type	Units of base currency	Pip value (dollar-quoted pairs)
Standard	100,000	10.00
Mini	10,000	1.00
Micro	1,000	0.10
Nano	100	0.01

Smaller denominations exist precisely so that a trader with a modest account can size a position to their intended risk rather than being pushed into an oversized one. If your account cannot support a micro lot at a sensible stop distance, the account is too small for the trade — not a reason to widen the risk.

Calculating pip value

The rule: pip value depends on the quote currency, the second one in the pair.

When the quote currency is your account currency. Straightforward. On EUR/USD with a dollar account, a standard lot gives 10 per pip, a mini lot 1, a micro lot 0.10.

When it is not. You must convert. On EUR/GBP with a dollar account, pip value is calculated in pounds and then converted to dollars at the current GBP/USD rate. Because that rate moves, so does your pip value — slightly, but it matters for precise sizing.

Yen pairs. The pip is 0.01 rather than 0.0001, and the pip value in yen must be converted to your account currency. On a standard lot of USD/JPY, one pip is 1,000 yen, which at a rate of 150 is roughly 6.67 dollars — not the 10 that many people assume by analogy with dollar-quoted pairs.

Most platforms display pip value automatically. It is worth being able to check it manually, because a sizing error caused by assuming the wrong pip value is silent until the loss arrives.

Position sizing, worked through

This is the calculation that determines outcomes.

Inputs:

• Account: 5,000
• Maximum risk per trade: 1%, so 50
• Stop distance: 25 pips
• Pair: EUR/USD, dollar account

Step 1. Value per pip you can afford:

50 / 25 pips = 2.00 per pip

Step 2. Convert to lots. A mini lot gives 1.00 per pip on this pair, so:

2.00 / 1.00 = 2 mini lots  (0.2 standard lots)

Step 3. Confirm. Two mini lots is 20,000 of exposure. A 25-pip adverse move costs 50, which is 1% of the account. Correct.

Change the stop to 50 pips and the position halves to one mini lot. The risk stays at 50. The risk is the fixed input; the size is the output.

The mistake this prevents

The common approach is to choose a position size first — often the largest the account permits — and then place a stop wherever seems reasonable. Risk per trade then varies unpredictably from perhaps 2% to 20%, and the trader has no idea which.

Running the calculation the other way round makes every loss the same size, which is what makes a sequence of losses survivable. Twenty consecutive losses at 1% leaves roughly 82% of the account. Twenty at 5% leaves about 36%.

Spread, in pips

The spread is quoted in pips and is paid on entry. A 1.2 pip spread on EUR/USD means the position starts 1.2 pips down.

That matters most for short-horizon strategies. A trade targeting 10 pips pays 12% of its target in spread before anything happens. A trade targeting 200 pips pays 0.6%. This single ratio explains much of why high-frequency retail strategies underperform: the cost is fixed per trade while the target shrinks.

Quick reference

Pair type	Pip location	Standard lot pip value
EUR/USD, GBP/USD, AUD/USD	4th decimal	10 USD
USD/JPY, EUR/JPY, GBP/JPY	2nd decimal	1,000 JPY, converted
USD/CHF, USD/CAD	4th decimal	In quote currency, converted
EUR/GBP, EUR/CHF	4th decimal	In quote currency, converted

The bottom line

Pips and lots are elementary, and skipping the arithmetic is the most common reason a trader cannot answer the only question that matters before opening a position: how much will this cost me if I am wrong?

Fix the risk. Measure the stop. Let those two determine the size. Everything downstream of that decision is easier.

This article is educational and is not financial advice. Leveraged foreign exchange trading carries a high risk of loss.