Lot Size for Oil, Silver and Other Commodities: A Practical Guide

Commodities are where position sizing goes wrong most often. On EUR/USD one lot is 100,000 units at nearly every broker. On oil, one lot can be 1,000 barrels at one broker and 100 at the next. Same "1 lot", ten times the risk.

The fix is always the same: stop thinking in pips, and use prices plus your broker's contract size.

The formula

Lots = (balance × risk %) ÷ (|entry − stop| × contract size)

• |entry − stop| is the stop distance in price, e.g. $0.60 on oil.
• Contract size is how many units one lot holds: barrels, ounces, MMBtu.

Multiply the two and you get what one lot loses if the stop is hit.

Find your contract size (the step everyone skips)

In MetaTrader, right-click the symbol in Market Watch → Specification. Look for:

• Contract size: units per lot. Use this directly.
• Or tick size and tick value: value of a 1.0 price move per lot = tick value ÷ tick size. A tick size of 0.01 with a tick value of $10 means $1,000 per 1.0 move, so the contract is 1,000 units.

On cTrader, open the symbol's info panel. On a prop firm platform, check their symbol specification page. If you can't find it, ask support. It's the one number you can't guess.

Oil (WTI and Brent)

Common contract sizes: 1,000 barrels (standard), 100 barrels, sometimes 10. Check yours.

Example on US Oil (WTI):

• Balance $10,000, risk 1% = $100
• Buy at 78.50, stop at 77.90, so $0.60 away
• 1,000 barrels per lot: $0.60 × 1,000 = $600 per lot

$100 ÷ $600 = 0.16 lots (rounded down). At a broker with 100-barrel lots the same trade is 1.66 lots. Size it in the US Oil calculator or UK Oil (Brent).

Natural gas

Natural gas moves a lot in percentage terms and contracts vary widely (10,000 MMBtu is common, many CFD brokers use less).

• Risk $100, buy at 2.850, stop at 2.780, so 0.070 away
• 10,000 MMBtu per lot: 0.070 × 10,000 = $700 per lot

$100 ÷ $700 = 0.14 lots. Natural gas gaps over weekends and around the weekly storage report, so a stop can fill worse than planned. Many traders size it smaller for that reason. Natural gas calculator.

Silver

Silver is usually 5,000 ounces per lot, 50 times gold's 100 oz, so small moves are expensive.

• Risk $100, buy at 30.50, stop at 30.20, so $0.30 away
• $0.30 × 5,000 = $1,500 per lot

$100 ÷ $1,500 = 0.06 lots. Sizing silver like gold is a classic way to blow a daily loss limit. Silver calculator, and see the gold guide for XAU/USD.

Platinum, palladium, copper and softs

Platinum, palladium, copper, wheat, corn, soybeans, sugar, coffee and cocoa have no standard CFD contract at all. The calculator leaves the contract size empty on purpose so you enter your broker's. Same formula, same Specification lookup: platinum, copper, coffee.

Non-USD accounts

Most commodities are priced in US dollars. On a EUR, GBP or other account, your risk is converted at the current exchange rate before sizing. The calculator does this with the latest rate, and you can overwrite it with your broker's.

Checklist before a commodity trade

1. Look up the contract size in your platform's Specification. Don't assume.
2. Measure the stop in price, not pips or points.
3. Run the numbers, and round the lot size down.
4. On gas and oil, allow for gaps around news and the weekly open.

Every commodity we support is in the free position size calculator. If you trade several accounts with different contract sizes, the Forexizer Calculator app saves each account's specs so you only look them up once.