Swap Calculator — Forex Overnight Rollover Fee Tool
Calculate the overnight swap (rollover) fee or credit for any forex position. Enter your trade size, pair price, and interest rates to instantly see daily, weekly, monthly, and total swap costs — and find out whether your position earns positive or negative carry.
Swap is shown in USD (account currency)
Number of standard lots (1 lot = 100,000 units)
Current EUR/USD exchange rate
Direction of your trade
Annual rate of the base currency (EUR)
Annual rate of the quote currency (USD)
How many overnight rollovers to calculate
Loading live rates…
Daily Swap
−$4.47
negative carry (you pay)
Notional Value
$108,696
Rate Differential
−1.50%
Carry Type
Negative (pay)
Wednesday Swap (3x)
−$13.40
Triple Swap Day
Weekly (7 nights)
−$31.27
Monthly (30 nights)
−$134.01
Annual (365 nights)
−$1,630.44
Total (5 nights)
−$22.33
Last reviewed · How we check our calculators
How to Use the Swap / Rollover Calculator
Using the swap calculator takes under a minute. Choose the currency pair, enter your trade size in lots (one standard lot = 100,000 units), the current pair price, and the annual interest rates for both the base currency and the quote currency. For crosses such as EUR/GBP the calculator also needs the quote currency's value in US dollars; it is prefilled from current rates and can be overridden. Each rate belongs to its currency: when you switch pairs, a currency you already entered keeps its rate, and a new one starts empty so you enter its rate. Select whether your trade is Long (buy) or Short (sell), then set the number of nights you plan to hold the position. The result updates as you type.
The calculator shows your daily swap in USD, plus projections for one week, one month, and the exact number of nights you entered. A green figure means you receive the swap (positive carry); a red one means you pay it (negative carry). Interest rates are usually available on your broker's contract specification page.
Note: On Wednesdays, most brokers apply a triple swap (3× the daily rate) to compensate for the weekend when markets are closed. The "weekly" figure in this calculator reflects 7 daily rollovers and therefore already includes this effect proportionally.
The Formula
This calculator uses the interest rate differential method, which is the academically correct basis for swap pricing:
- Notional (quote currency): Notional = Lots × 100,000 × Pair Price
- Notional in USD: multiply by the USD value of one unit of the quote currency — 1 for X/USD pairs, 1 ÷ Pair Price for USD/X pairs (so USD/JPY notional is simply Lots × $100,000), and the quote currency's USD rate for crosses
- Rate differential (long position): Rate Diff = Long Currency Rate − Short Currency Rate
- Rate differential (short position): Rate Diff = Short Currency Rate − Long Currency Rate
- Daily swap (USD): Daily Swap = Notional in USD × (Rate Diff / 100) / 365
- Total swap: Total = Daily Swap × Number of Nights
A positive Daily Swap means you receive this amount each night (positive carry). A negative value means you pay it. The sign depends on which currency in the pair carries the higher interest rate and which direction you are trading.
Brokers may quote swap rates directly in pips (the "swap rate" column on their platform). Those rates include broker markup and may differ slightly from the pure interest rate differential shown here. Always verify with your broker's published swap schedule for live trading.
Practical Examples
Example 1 — Positive Carry: Long USD/JPY
You buy 2 lots of USD/JPY at 149.50. The USD interest rate is 5.25% and the JPY rate is 0.1%. You plan to hold for 5 nights.
- Notional = 2 × 100,000 × 149.50 = ¥29,900,000 = $200,000 (USD is the base currency)
- Rate differential (long) = 5.25% − 0.1% = 5.15%
- Daily swap = $200,000 × 0.0515 / 365 = +$28.22/day
- Total for 5 nights = +$141.10 (receive)
Because USD carries a much higher interest rate than JPY, a long USD/JPY position earns positive carry — a classic "carry trade" setup. Note that the yen notional must be converted to dollars first: applying the rate to ¥29.9 million as if it were dollars would overstate the swap about 150-fold.
Example 2 — Negative Carry: Long EUR/USD
You buy 1 lot of EUR/USD at 1.0850. The EUR rate is 3.75% and the USD rate is 5.25%. You hold for 7 nights.
- Notional = 1 × 100,000 × 1.0850 = $108,500
- Rate differential (long) = 3.75% − 5.25% = −1.50%
- Daily swap = $108,500 × (−0.015) / 365 = −$4.46/day
- Total for 7 nights = −$31.21 (pay)
Because the USD funding rate exceeds the EUR rate, holding long EUR/USD costs you swap fees each night. Over weeks and months this adds up, and is an important cost to factor into any carry-sensitive trading strategy.
Example 3 — Cross Pair: Long EUR/GBP
You buy 1 lot of EUR/GBP at 0.8500 with EUR at 2.00% and GBP at 4.00%, holding for 10 nights. GBP/USD trades at 1.2700, so one pound is worth $1.27.
- Notional = 1 × 100,000 × 0.8500 = £85,000 × 1.27 = $107,950
- Rate differential (long) = 2.00% − 4.00% = −2.00%
- Daily swap = −$5.92/day; total for 10 nights = −$59.15 (pay)
Frequently Asked Questions
A forex swap (also called a rollover) is the interest credit or debit applied to your account when you hold an open position overnight past the daily settlement cutoff (typically 5 PM New York time). It arises from the interest rate differential between the two currencies in the pair. If the currency you are long carries a higher interest rate than the one you are short, you receive the swap. If it carries a lower rate, you pay it. Brokers add a small markup to cover their costs.
Most forex brokers apply three times the normal daily swap on Wednesday night (settling on Friday). This compensates for Saturday and Sunday, when the market is closed but interest still accrues. As a result, your Wednesday swap debit or credit is 3× the amount shown for other days. Some brokers apply the triple swap on a different day — check your broker's schedule to be sure.
Use the central bank policy rates for each currency: the Federal Reserve rate for USD, the ECB rate for EUR, the Bank of Japan rate for JPY, and so on. Your broker's contract specifications page will also show published swap rates (in pips or currency) directly, which already incorporate the differential and broker markup. For educational calculations, central bank rates give the most transparent result.
A carry trade is a forex strategy where you deliberately buy a currency with a high interest rate and sell a currency with a low interest rate to earn the positive daily swap. Classic examples include long AUD/JPY or long USD/JPY during periods of large rate differentials. While the swap income can be attractive, carry trades are exposed to sudden reversals when market risk appetite drops, often causing rapid currency moves that dwarf the accumulated swap income.
Yes — swap scales linearly with notional value. A 2-lot position earns or pays exactly twice the swap of a 1-lot position, because the notional value is doubled. Larger positions accumulate swap costs (or benefits) proportionally, which is why carry traders often use large lot sizes while swing traders are more sensitive to overnight costs eating into their profit targets.
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