Lot Size
Lot size is the standard trading unit of an instrument — for example 100,000 units of currency in a standard forex lot.
Many markets are traded in fixed units called lots. In forex a standard lot is 100,000 units of the base currency; futures have contract sizes set by the exchange; many share markets trade in round lots. The lot size decides how much each price move is worth, so choosing it is really choosing your risk. This entry explains common lot sizes, how they connect to pip value, and how to pick a size from your risk.
- Category
- Market Structure
- Reading time
- 4 min
- Also called
- Lot, Standard lot, Mini lot
- Updated
Lot size in plain words
Because currency moves are tiny, forex is traded in micro lots, mini lots and standard lots: 1,000, 10,000 or 100,000 units of currency.1 A bigger lot makes every pip worth more. See Pip Value.
In a currency pair, the units are in the base currency — the first one in the quote.2 So one standard lot of EUR/USD is €100,000. See Trading Pair.
How to choose a lot size, step by step
Decide your risk in money
For example 1% of the account. See Risk per Trade.
Set the stop in pips
From the setup, not from the lot size. See Stop Loss.
Find the pip value per lot
About $10 per standard lot on USD-quoted pairs.
Divide
Lots = risk ÷ (stop in pips × pip value per lot).
Round down
Use micro lots for fine-tuning; never round up past your risk.
Check margin
Leverage determines how much margin the position ties up. See Margin.
Worked examples
Example 1 — Lots and pip value
ScaleEUR/USD, pip value per standard lot $10.
| 1 standard lot | $10 per pip |
| 1 mini lot | $1 per pip |
| 1 micro lot | $0.10 per pip |
Lot size scales the money value of every move.
Example 2 — Sizing from risk
SizingAccount $8,000, risk 1% ($80), stop 20 pips on EUR/USD.
| Lots | $80 ÷ (20 × $10) = 0.4 standard lots |
| In units | 40,000 (4 mini lots) |
The stop and the risk decide the size — not a habit of always trading “one lot”.
Example 3 — The “one lot” habit
OversizedA trader with a $2,000 account always trades 1 standard lot with a 30-pip stop.
| Risk per trade | 30 × $10 = $300 (15% of the account) |
A fixed lot size ignores account size and stop distance. See Position Sizing.
Common lot sizes in forex
| Aspect | Units of base currency | Pip value (USD-quoted pair) |
|---|---|---|
| Standard lot | 100,000 | ≈ $10 |
| Mini lot | 10,000 | ≈ $1 |
| Micro lot | 1,000 | ≈ $0.10 |
| Nano lot (some brokers) | 100 | ≈ $0.01 |
Why lot size matters
Risk control
The lot size is your risk dial.
Small accounts
Micro lots allow precise sizing with little capital.
Margin planning
Larger lots need more margin. See Leverage.
Comparing instruments
Contract sizes differ between markets. See Futures Contract.
Advantages and disadvantages
Advantages
- Standard units make orders and pricing simple.
- Smaller lots allow precise risk control.
- Links directly to pip value and margin.
Disadvantages
- Lot conventions differ between brokers and products.
- Standard lots are too large for small accounts.
- Easy to oversize by trading a habitual number of lots.
Going deeper
Read as far as you need. Each level builds on the one before it.
Lots are units, not risk
Beginner
Two traders with one lot each can have very different risk if their stops differ. Always size from risk.
Fractional lots
Intermediate
Many platforms accept sizes like 0.37 lots. That flexibility lets you match risk precisely instead of rounding to whole lots.
Leverage and lot size
Advanced
Leverage lets a small deposit control a large lot, which magnifies both gains and losses and can lead to losses greater than the initial capital.3
Common mistakes
Always trading the same lot size
Recalculate from risk and stop.
Confusing lots and units
Check your platform’s convention.
Ignoring pip value differences
Non-USD pairs have different pip values.
Rounding up
Round down to stay within risk.
Check your understanding
Test yourself before moving on. Each answer comes with an explanation.
Key points to remember
- Forex lots: standard 100,000, mini 10,000, micro 1,000 units.
- Units are in the base currency.
- Lot size scales pip value and risk.
- Size lots from risk and stop distance.
- Leverage makes oversized lots dangerous.
Frequently asked questions
What lot size should a beginner use?
How much is one standard lot?
Are lot sizes the same at every broker?
Further learning
- Pip Value
How lot size turns pips into money.
- Position Sizing
Choosing size from risk.
- Leverage
Why large lots are risky.
- Margin
What each lot ties up.
Sources
This article is written in our own words. The sources below support the specific facts, rules and figures marked with a number in the text. Links open the original publisher’s page.
- IG. Pip value definition (opens in a new tab) Checked .
- IG. What are forex CFDs and how do you trade them? (opens in a new tab) Checked .
- Investor.gov (SEC). Foreign Currency Exchange (Forex) Trading For Individual Investors (opens in a new tab) Checked .
Educational content, not financial advice. Examples use hypothetical prices and simplified costs; actual fees, margin rules and regulations vary by broker, market and country. We are not affiliated with any publisher linked above. Last reviewed . Report an error or request a source credit.