Lab · Devtool
Funding Rate Arbitrage Calc is a free online tool that calculates perp funding, annualised funding rate, fees, breakeven and net P&L for a cash-and-carry trade — long spot, short perp — from prices and a funding rate you enter yourself.
Cash-and-carry trade
Cash-and-carry means holding the same exposure in two places: long the spot asset and short the perpetual contract. If the perp trades above spot, that gap is the basis. While you hold the pair, funding is exchanged between longs and shorts at each interval: when the funding rate is positive, longs pay shorts, so your short leg collects; when it is negative, your short leg pays.
The maths on this page: basis = perp − spot; funding per interval = notional × funding rate; funding per day = per-interval funding × (24 ÷ interval hours); annualised rate = funding rate × intervals per day × 365; cumulative funding = daily funding × holding days; fees = notional × (spot fee % + perp fee %). Headline net P&L = cumulative funding − fees. If the perp converges to spot when you exit, you also gain basis × quantity, where quantity = notional ÷ spot price.
Educational demo only — not trading advice. All funding rates here are entered by you; this page fetches no live market data, places no trades, and ignores leverage, margin, liquidation, slippage, and exit-price moves. Real funding rates change every interval and can flip sign without warning.