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Compare Forex Brokers UK

Forex Trading Calculators

I built all Five calculators on one data spine, so the numbers stay consistent wherever you check them. Our own UK spread captures completed with the August 2026 measured programme; you will see the date on every exchange rate, and the leverage maths follows the FCA's retail caps rather than an offshore default.

Justin Grossbard, Co-Founder of CompareForexBrokers Written by Justin Grossbard Fact-checked by David Levy Last updated:
One pip is worth £7.40 US$10.00 at 0.7399 GBP per USD · rate dated 2 September 2026
Same maths as the full calculator Full pip value calculator →

What will trading cost me?

One tool, built on broker spreads

Broker Cost Calculator

Your monthly trading cost across every FCA-regulated broker. Our UK spread captures completed in August 2026; cost comparisons will return with them.

Needs
pairs traded · trades per month · lot size
Returns
ranked monthly cost per broker, in GBP

Behind the ranking

FCA brokers scored
29
Pairs covered
3
Spread dataset
August 2026
Data source
Live accounts

How much should I risk?

Position sizing and margin, worked back from risk

  • Position Size Calculator

    Lots to trade for your balance, risk and stop distance.

    Needs
    balance · risk % · stop pips
    Returns
    lots and units to trade
    Pure maths, no broker data Open calculator →
  • Margin Calculator

    Margin a position ties up under the FCA's retail leverage caps, tier by tier.

    Needs
    pair · lots · leverage tier
    Returns
    required margin in GBP
    FCA caps applied Open calculator →

What is the trade worth?

Pips, and profit or loss

  • Pip Value Calculator

    What one pip is worth in your account currency. The figure the other calculators consume.

    Needs
    pair · lot size · account currency
    Returns
    pip value in GBP, USD or EUR
    Dated FX rates Open calculator →
  • Profit / Loss Calculator

    Profit or loss for an entry, exit and position size, long or short.

    Needs
    entry · exit · size · direction
    Returns
    result in account currency
    Dated FX rates Open calculator →

Which calculator answers your question

I've grouped these five tools by the question you're asking, not by instrument. If you know your question but not the calculator, start here.

What will a month of trading cost me?
The broker cost calculator, then the lowest spread and lowest commission guides for the brokers behind the ranking.
How many lots should I trade?
The position size calculator, which works back from a risk percentage and a stop distance rather than from a lot size.
What is a pip worth on this pair?
The pip value calculator. It is the figure the other four consume, so it is the one to check when a result looks wrong by a factor of ten.
How much margin does this position tie up?
The margin calculator, with the caps explained in our leverage guide and the mechanics in our margin guide.
What would this trade have made or lost?
The profit and loss calculator, worked through in full in our CFD trading examples.

Where the figures come from

Every figure the tools output is traceable. Broker spreads and commissions render from the same advertised dataset our best forex brokers in the UK rankings use. Exchange rates carry their capture date (2 September 2026 at this build). The margin tiers quote the FCA's COBS 22.5 rules directly, and where a number is missing the tools say so instead of estimating. Our own UK spread captures completed with the August 2026 measured programme. The scoring model is on our methodology page.

  • 13currency pairs on the shared spine
  • 29FCA brokers in the scored roster
  • 3account currencies: GBP, USD, EUR
  • 30:1FCA retail cap on major pairs, applied by the margin maths

I use the FCA's list of 6 major currencies to set the leverage cap for each pair. Each calculator tells you which part of the spine it draws on, and points you to the tool that handles the rest.

  • Spread dataset: August 2026
  • FX rates: dated on every result
  • Margin tiers: FCA COBS 22.5, quoted directly

Calculator questions, answered

Why do results differ from my broker's calculator?

Broker calculators use their own live feed and sometimes their own contract sizes. Ours use a dated mid rate and standard 100,000-unit lots, and state both, so small differences are expected and explainable.

Do the calculators work for MT4 and MT5 lot conventions?

Yes. Standard, mini and micro lots follow the 100,000, 10,000 and 1,000 unit conventions MT4 and MT5 use, and the position size tool shows the lots to trade, with units alongside them in the quick calculator above.

How current are the spread figures?

The cost calculator uses advertised spreads from FCA-regulated brokers. Our own UK spread captures completed with the August 2026 measured programme.

Are these calculators free, and do they need an account?

All 5 are free with no sign-up. They run in the page, send nothing to a broker and are not connected to any trading account.

Keep going: the guides behind the tools