GBPUSD position size calculator

Size a pound–dollar trade from your risk and stop: 100,000 pounds per lot, $10 a pip, converted at the pair's price on a GBP account.

Updated 31 October 2026

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How sizing works on cable

GBPUSD, nicknamed cable, is the price of one British pound in US dollars. A lot is 100,000 pounds, a pip is 0.0001, and one pip on one lot is $10 — $0.10 on 0.01 lot. On a USD account that value is fixed. On a GBP account the calculator converts the dollar loss at the GBPUSD price you enter, so at 1.3450 a pip per lot is $10 ÷ 1.345 = £7.43. On any other account currency, type the rate from dollars to your currency, or the calculator uses a reference rate from 27 September 2026 and labels the result an estimate.

A worked example: an 18-pip stop

A $10,000 USD account risking 1% has $100 to lose. With an 18-pip stop one lot loses 18 × $10 = $180; 100 ÷ 180 = 0.556, rounded down to 0.55 lots, an actual risk of $99.00.

On a £10,000 GBP account at 1.3450 the risk is £100. One lot loses 18 × £7.435 = £133.83 at the stop, the raw size is 0.747 and the position 0.74 lots, risking £99.03. A pound buys more than a dollar, so the same percentage risk on a GBP account is more money and more lots.

Volatility and typical stops

Cable usually moves more than EURUSD in pips each day and reacts sharply to UK inflation, jobs and Bank of England news as well as to US data. Its spreads are slightly wider than EURUSD's on most accounts. Intraday stops of 12 to 30 pips are typical for setups in London or New York, and a stop that works on EURUSD is often too tight for cable. A wider stop with a smaller lot keeps the money at risk the same — the calculator does that arithmetic. These are general tendencies, not a forecast.

Cable sessions and Kill Zones

Most of cable's volume comes from London. The London Kill Zone (02:00–05:00 New York time) contains the 07:00 London data releases and the London open at 03:00 New York; the New York AM Kill Zone (07:00–10:00) covers US data at 08:30 and the London–New York overlap. The Asian Kill Zone (20:00–00:00) is usually the quietest stretch. Convert the windows to your own clock with the Kill Zone converter; today's sessions and news are on the GBPUSD market page.

Common GBPUSD sizing mistakes

• Copying a EURUSD stop and lot. The pip value is the same $10, so the lot is only right if the stop is right for cable's wider range.
• Forgetting the conversion on a GBP account. At 1.3450 a pip is £7.43, not £10; sizing at £10 a pip trades about 26% fewer lots than the plan allows.
• Sizing a tight stop just before 07:00 London data or a Bank of England decision without allowing for the wider spread and slippage.
• Confusing GBPUSD with GBPJPY: the yen cross has a pip of 0.01 and a pip value in yen that changes with USDJPY.

See the EURUSD calculator for the euro, or the main calculator for GBPJPY and other crosses; the method is in how to calculate position size.