Position Size Calculator
Size a forex, futures, crypto, metals or stock trade from the risk you choose — in lots, contracts, coins or shares, rounded down to a size your broker takes, with what it really risks after rounding.
Size it here. Review it in the Journal.
The same calculator lives in the Journal's Risk Desk, with one more button: log the sized plan as a trade, so the size you planned is what your review measures the execution against. Try it in the free demo — no account needed.
How the size is worked out
Position size is the money you are prepared to lose divided by what one unit of size loses if the stop is hit:
size = (balance × risk %) ÷ (stop distance × value per point × exchange rate)
Take an NQ long at 19,700 with the stop at 19,676, on a $100,000 account risking 1%. The money at risk is $1,000. NQ pays $20 a point, so the 24-point stop costs $480 a contract. $1,000 ÷ $480 is 2.08 contracts — the order is 2, and it risks $960, 0.96% of the account.
The size is always rounded down to the broker's step. Rounding up would put more at risk than the plan allows, so the calculator shows the real figure after rounding beside the plan instead.
What one unit is worth
The presets use these specifications. Check your broker's contract page if unsure.
| Instrument | One unit | Value of a move | Smallest step |
|---|---|---|---|
| Forex (EURUSD, GBPUSD…) | 1 lot = 100,000 base units | $10 per pip on a USD-quoted pair | 0.01 lot |
| Forex JPY pairs (USDJPY…) | 1 lot = 100,000 base units | ¥1,000 per pip (0.01) | 0.01 lot |
| XAUUSD (gold) | 1 lot = 100 oz | $100 per $1 move | 0.01 lot |
| XAGUSD (silver) | 1 lot = 5,000 oz | $5,000 per $1 move | 0.01 lot |
| ES / MES | 1 contract | $50 / $5 per point (tick 0.25) | 1 contract |
| NQ / MNQ | 1 contract | $20 / $2 per point (tick 0.25) | 1 contract |
| YM / MYM | 1 contract | $5 / $0.50 per point (tick 1) | 1 contract |
| RTY / M2K | 1 contract | $50 / $5 per point (tick 0.1) | 1 contract |
| CL / MCL | 1 contract | $1,000 / $100 per $1 (tick 0.01) | 1 contract |
| GC / MGC | 1 contract | $100 / $10 per $1 (tick 0.1) | 1 contract |
| Crypto (BTC, ETH, SOL…) | 1 coin | $1 per $1 move, per coin | 0.0001 BTC · 0.001 ETH · 0.01 SOL |
| US stocks | 1 share | $1 per $1 move, per share | 1 share (or fractional) |
Position sizing questions
How is position size calculated?+
It is the money you are willing to lose divided by what one unit of size loses if the stop is hit. The money at risk is the account balance times the risk percentage; the loss per unit is the stop distance times the instrument's value per point, converted to the account currency.
Why does the calculator round the size down?+
A broker only takes sizes in fixed steps: 0.01 lots, whole contracts, whole shares. Rounding up would risk more than you planned, so the size is always rounded down and the real risk after rounding is shown next to your plan.
What if even the smallest size risks more than my plan?+
The calculator says so instead of giving a size. The choices are a tighter stop, a smaller contract such as a CME micro, or passing on the trade.
How are pairs like USDJPY handled for a USD account?+
USDJPY pays in Japanese yen. When your account currency is the pair's base currency, the calculator converts at the pair's own price. For a pair with no leg in your account currency, such as EURJPY on a USD account, it asks for the exchange rate rather than guessing one.
Does it include spread, commission or slippage?+
No. It sizes to the stop distance you enter. To allow for costs, widen the stop by the expected spread and slippage, or lower the risk percentage.
Is position value the same as margin?+
No. Position value is the notional size of the trade. The margin a broker holds is a fraction of it and depends on the broker, the instrument and the leverage.