i What this calculator does
This calculator works out the actual Rand cost of the bid-ask spread on a trade, the built-in cost you pay simply by entering and exiting a position, based on the spread size and your position size.
Enter the spread in pips, the pip value for your position size, and your account currency conversion if needed, and the calculator returns the exact cost in Rand.
This calculator is for educational purposes only and uses a standard pip value approximation. Actual costs vary by instrument, broker, and account currency.
Frequently asked questions
How is the spread cost actually calculated?
Spread cost equals the spread size (in pips or points) multiplied by the pip value for your position size. This calculator uses a standard pip value approximation, your actual cost may vary slightly depending on your specific instrument and account currency.
Is spread cost a one-time cost or does it repeat?
It's effectively a one-time cost per round-trip trade, paid once when you open and effectively realise it when you close, since you buy at the ask and sell at the bid. It's not charged repeatedly like an overnight swap fee.
Does a wider spread always mean a worse broker?
Not necessarily, spread width often reflects genuine liquidity and instrument type rather than broker quality alone. Compare TOTAL cost (spread plus any separate commission) across brokers for a fairer comparison, rather than judging spread width in isolation.
How does position size affect spread cost?
Spread cost scales directly with position size, doubling your position size doubles your spread cost in Rand terms, since the same pip spread now applies to a larger notional position.
Does the spread cost apply even if I close the trade at a profit?
Yes, the spread is a cost baked into the transaction itself, you effectively pay it the moment you open and close the position, regardless of whether the trade ultimately closes in profit or loss.
Why do spreads widen during major news events?
Liquidity providers pull back or widen their pricing during high-uncertainty moments to protect themselves from rapid price swings, which is why spreads on the same instrument can look very different around scheduled news releases.
Is a fixed spread always better than a variable one?
Not necessarily, fixed spreads offer predictability but are sometimes wider on average, while variable spreads can be tighter in calm conditions but widen unpredictably during volatility, the better choice depends on your trading style.
Does this calculator account for commission separately?
No, this specifically calculates spread cost. If your broker also charges a separate commission per trade, add that using our Trading Cost Calculator for the full combined cost picture.
How much does spread cost typically eat into a scalper's profits?
Meaningfully more than for longer-term traders, since scalpers target small price moves and trade frequently, the spread represents a proportionally larger share of each trade's target profit, making tight spreads especially important for this style.
Want to embed this calculator on your site?
Embed this calculator
Free to use on your own site. Copy the code below and paste it where you want the calculator to appear.
<iframe src="https://www.tradeanswers.co.za/embed/bid-ask-spread-cost-calculator.html"
width="100%" height="570" style="border:0;max-width:520px"
title="Bid-Ask Spread Cost Calculator - TradeAnswers" loading="lazy"></iframe>
<p><a href="https://www.tradeanswers.co.za/bid-ask-spread-cost-calculator.html">Bid-Ask Spread Cost Calculator</a> by <a href="https://www.tradeanswers.co.za/">TradeAnswers</a></p>