What this lot size calculator does
Choosing a lot size is the decision that sets how much money moves with every tick. Too large and a normal stop wipes out a big part of the account; too small and a good trade barely registers. This lot size calculator works out the number of lots to trade so that hitting your stop loss costs a fixed amount you have chosen in advance.
It covers forex pairs, gold, silver, oil, index CFDs such as NAS100 and US30, and crypto CFDs, so you can size positions consistently across very different markets.
Lot sizes explained
In forex, lots are standardised:
| Lot | Units of base currency | EURUSD pip value |
|---|---|---|
| 1.00 standard | 100,000 | $10 |
| 0.10 mini | 10,000 | $1 |
| 0.01 micro | 1,000 | $0.10 |
Other markets use their own contract sizes. Common CFD specs are:
- Gold (XAUUSD): 1 lot = 100 oz. A $0.10 move (one pip by the usual convention) is $10 per lot; a $1 move is $100 per lot.
- Silver (XAGUSD): 1 lot = 5,000 oz.
- Oil: usually 1,000 barrels per lot, sometimes 100.
- Indices such as NAS100: usually $1 per index point per lot, though some brokers use 10 or 0.1.
- Crypto CFDs: usually 1 lot = 1 coin.
These vary, so check your broker's contract specification and adjust the contract size in the calculator if needed.
The formula
Risk amount = Balance × Risk % ÷ 100
Lots = Risk amount ÷ (Stop distance in pips × Pip value per 1 lot)
For indices, the "pip" is one index point. For gold it is $0.10, so an $8 stop is 80 pips.
Worked example: same risk, gold vs NAS100
You have a $5,000 USD account and decide to risk 2% per trade, which is $100.
Gold trade. Your stop is $8.00 away from entry, which is 80 pips at $0.10 per pip. One lot of gold is worth $10 per pip.
- Lots = 100 ÷ (80 × 10) = 0.125 lots
- Most brokers allow steps of 0.01, so round down to 0.12 lots.
- Check: 0.12 × 100 oz × $8.00 = $96 lost if the stop is hit.
NAS100 trade. Your stop is 60 index points away. Assuming $1 per point per lot:
- Lots = 100 ÷ (60 × 1) = 1.67 lots (1.666…)
- Round down to 1.66 lots.
- Check: 1.66 × 60 points × $1 = $99.60 at risk.
Both trades risk about the same money with very different lot sizes: lot size is an output of risk and stop, not a habit. If your broker's NAS100 contract is $10 per point instead, the correct size becomes ten times smaller, which is why the contract field matters.
How to use this calculator
- Select the instrument and confirm the contract size matches your broker.
- Enter your account balance and account currency.
- Enter the risk, either as a percentage or as a fixed amount.
- Enter your stop loss distance in pips or points (or the entry and stop prices).
- Read the suggested lot size and round it down to your broker's minimum step.
Rounding and minimum lot steps
Brokers usually trade in steps of 0.01 lots, with a minimum of 0.01. Always round down, never up, so that the real risk stays at or below your plan. With very small accounts and wide stops, the correct size may come out below 0.01 lot. In that case the only ways to stay within your risk are a tighter stop, a smaller instrument, or skipping the trade.
Some index and crypto CFDs have larger minimum sizes, such as 0.1 or 1 lot. Check the minimum volume in your platform's symbol specification.
Lot size vs margin
The lot size you get here controls risk, but it also decides the margin your broker will hold. A correctly risk-sized gold position can still need more margin than you expect, particularly at low leverage. Run the size through the margin calculator to confirm you have enough free margin. If you prefer to work strictly with a percentage of balance on forex pairs, the position size calculator walks through that method in more detail, and the pip value calculator shows the pip value used in the formula.
Frequently asked questions
What lot size should I use for a $1,000 account?
It depends on your stop distance and risk. Risking 1% ($10) with a 20 pip stop on EURUSD gives 10 ÷ (20 × 10) = 0.05 lots. A wider stop would mean a smaller size.
Is 0.01 lot safe?
No lot size is safe or unsafe on its own. 0.01 lot on EURUSD is $0.10 per pip, but on some CFDs 0.01 lot can carry much more exposure. Judge size by the money at risk at your stop.
How do I calculate lot size for gold?
Convert your stop to pips ($0.10 each), then divide your risk amount by stop pips × $10. A $5 stop is 50 pips; risking $50 gives 50 ÷ (50 × 10) = 0.10 lots.
Why is my NAS100 lot size so large compared with forex?
Index CFDs are often priced at $1 per point per lot, and indices move many points a day. To risk the same money, you may need more lots than you would on a currency pair.
Should I round the lot size up or down?
Down. Rounding up increases the loss if your stop is hit, even if only slightly.
Closing note
A lot size calculator keeps every trade inside the same risk budget, whether you are trading EURUSD, gold or the Nasdaq. Confirm the contract size with your broker, size from your stop, and round down.
Trading leveraged products carries a high risk of loss. Results are estimates; check your broker's contract specifications.