Forex Swap & Rollover Cost Calculator

What a swap actually is

A swap (also called a rollover or overnight financing fee) is the interest adjustment applied to any forex or CFD position you hold past the broker's daily rollover time — typically 21:00 UTC. Every currency pair is two currencies with two different interest rates. When you hold the pair overnight, you are effectively long one currency's rate and short the other's. The difference between those two rates is settled on your position each night as a credit or a debit.

Because the two sides of a pair have different rates, the swap is directional: a long position and a short position on the same pair carry different numbers. That is why a calculator needs to know which way you are facing — swapRate = long ? swapLong : swapShort. One side is usually a charge and the other a (smaller) credit, with the gap covering the broker's financing margin.

The formula

This tool computes the cost in three steps:

swapRate = direction is long ? swapLong : swapShort   // per lot, per night
daily    = lots × swapRate                            // one night's cost
total    = daily × nights                             // across N nights

swapRate is the per-lot, per-night figure your broker publishes for that symbol (a currency amount or a points/pip value the platform converts to your account currency). A negative total means you pay; a positive total means you are credited. Multiplying by lots scales a per-standard-lot rate to your actual position, and multiplying by nights extends it across the holding period.

The Wednesday triple-swap rule

Spot forex settles T+2 (two business days after the trade). To account for the weekend, when the value date rolls over a weekend the swap is multiplied. In practice the industry convention is that the Wednesday-to-Thursday roll is charged at triple (3×) the normal rate, because it carries Saturday and Sunday's financing forward. So if your holding period includes a Wednesday night, that one night counts as three. This calculator applies the Wednesday triple weighting when counting nights, so a position open across a Wednesday is not under-costed.

Worked example

Say you go long 2.5 lots of a pair whose published long swap is −7 USD per lot, per night, and you plan to hold it for 4 nights, one of which is a Wednesday.

1. Direction is long, so swapRate = swapLong = −7.
2. daily = 2.5 × (−7) = −17.50 USD per ordinary night.
3. Nights: 3 ordinary nights + 1 Wednesday counted as 3 = 6 effective nights.
4. total = −17.50 × 6 = −105.00 USD.

You would pay roughly 105 USD in financing over those four calendar nights. Flip to the short side, where the published rate might be only −1.2 USD per lot, and the same hold costs 2.5 × −1.2 × 6 = −18.00 USD — a reminder that direction matters as much as size.

Edge cases and pitfalls

• Positive swaps are not free money. A favourable rate differential can credit your account, but rates move, brokers adjust the financing margin, and a credit on one leg rarely offsets the risk of holding the position. Carry is a strategy, not a guarantee.
• Triple-swap days shift on holidays. The 3× roll usually lands on Wednesday, but around market holidays a broker may move the triple charge to another weekday. Check the symbol specification before assuming Wednesday.
• Gold and exotics bite hardest. Metals like XAUUSD and high-yield FX pairs often carry large, lopsided swaps. A position that looks profitable on price can leak its edge to overnight financing if you hold it for weeks — exactly the trap covered in our gold carry write-up.

Where FXNX fits

FXNX publishes a real swap rate against every one of its 150+ instruments — nothing hidden behind a tier — and selected FX and metals symbols qualify for Islamic, swap-free conditions. Plug your published rate into the fields above to size the true cost before you hold.