Perpetual Funding Rate Cost Calculator
Calculate the total funding payments you will pay or earn on a perpetual futures position over a given holding period. Essential for traders assessing the carry cost of holding perp positions overnight or for days.
About this calculator
Perpetual futures contracts have no expiry date, so exchanges use a funding rate mechanism to keep the contract price anchored to the spot price. Traders on the dominant side (long or short) pay the other side at regular intervals — typically every 8 hours, meaning 3 fundings per day. The total funding cost formula is: fundingCost = positionSize × (fundingRate / 100) × daysHeld × fundingsPerDay. A positive funding rate means longs pay shorts; a negative rate means shorts pay longs. Funding rates are expressed per interval and can be annualized for comparison. For leveraged positions, funding is calculated on the full notional position size, not just the margin, so carrying large leveraged positions for extended periods can significantly erode returns even if the trade direction is correct.
How to use
You hold a $50,000 long BTC perpetual position. Funding rate = 0.01% per interval, 3 fundings per day, held for 7 days. Step 1: fundingCost = 50,000 × (0.01 / 100) × 7 × 3. Step 2: 50,000 × 0.0001 = $5 per interval. Step 3: 5 × 7 × 3 = $105 total paid over 7 days. This $105 is deducted from your PnL regardless of price movement. Enter your position details to see your exact carry cost before sizing a trade.
Frequently asked questions
What is a funding rate and how does it work on perpetual futures exchanges?
The funding rate is a periodic payment exchanged between long and short traders on a perpetual futures exchange. It is designed to keep the perpetual contract price close to the underlying spot price. When the perpetual trades at a premium to spot, longs pay shorts to incentivize more shorting and less longing. Rates are typically settled every 8 hours and can range from near zero to over 0.1% per interval during highly bullish or bearish periods.
How much does funding rate cost eat into my perpetual futures profits over time?
Funding costs compound over holding periods and can meaningfully reduce profits, especially for highly leveraged positions held during high-funding-rate environments. At 0.01% per interval with 3 daily fundings, a $100,000 position pays $30 per day — $210 per week, $900 per month. During bull markets, funding rates can spike to 0.1% or higher per interval, increasing costs tenfold. Traders should factor annualized funding costs into their expected return calculations before holding perp positions for extended periods.
When should I consider the funding rate before opening a perpetual futures position?
Funding rate becomes a significant concern whenever you plan to hold a position for more than a few hours, especially in trending markets where rates skew heavily in one direction. If you are on the paying side (typically longs in bull markets), high funding eats into profits and can turn a winning directional trade into a net loss. Monitoring the current and historical funding rate on your exchange helps you assess whether the carry cost is justified by your expected price move. Some traders deliberately take the receiving side of funding as a yield strategy.