Perpetual Funding Arbitrage Calculator
Free perpetual funding rate arbitrage calculator. Long spot + short perp = delta-neutral funding harvest. Compute APR, fees, breakeven funding rate.
Risks: liquidation on perp leg if margin too low, exchange counterparty, funding inversion (paying instead of collecting). Maintain ≥3x maintenance margin on perp.
How to use Perpetual Funding Arbitrage Calculator
This Perpetual Funding Arbitrage Calculator models the cash-and-carry trade: you go long the same dollar amount on spot and short it on a perpetual future, cancelling directional price exposure so the only return is the funding payment. Per interval it computes position size times funding rate (size × funding%/100); since you are short the perp, a positive funding rate pays you and a negative rate costs you. It multiplies that by intervals per day times days held to get total funding income.
From there it subtracts trading costs — fee% applied four times (entry and exit on both the spot leg and the perp leg) — to give net P&L and net return %. It annualizes funding APR as daily funding / size × 365, and net APR as net profit / size × 365/days. The break-even funding per interval = fee% × 4 / (intervals × days) tells you the minimum rate that just covers fees. Compare the headline yield against our <a href="/apy-apr-calculator/">APY/APR calculator</a> to weigh it versus simpler staking.
Input guide and assumptions
Position Size (each leg) is the dollar notional placed on both spot and perp — keep them equal for true delta-neutrality. Funding Rate per interval (%) is the rate the exchange charges; preset chips cover -0.03% to 0.1%. Funding Intervals per Day maps to settlement cadence: 1 = every 24h, 3 = every 8h (the common default), 24 = hourly. Trading Fee per Side (%) is your taker/maker fee per fill; Days Held drives both the totals and the annualization.
The model assumes a perfectly hedged 50/50 position with no slippage, no borrow cost on the spot leg, and a constant funding rate over the whole period — real funding swings interval to interval and can flip negative, turning income into a cost. Fees are counted as four discrete trades; spreads and partial fills are ignored. It also excludes liquidation risk on the perp leg: keep at least 3× maintenance margin, since a margin call can break the hedge and erase the carry.
Reading basis trade returns
Perpetual funding arbitrage exploits the funding rate paid by perp longs to shorts (when rate is positive) or vice versa. Strategy: hold equal-size long spot + short perp = delta-neutral. Profit = funding rate × position × intervals - trading fees. At 0.05% per 8-hour interval (3 daily), that's 0.15%/day × 365 = 54.75% APR before fees.
Real-world annualized returns range 8-50% depending on market conditions (bull funding 0.05-0.2%, bear/neutral -0.05% to 0.02%). After 4 trading legs (open spot + open perp + close perp + close spot at typical 0.04% each = 0.16% total), break-even funding rate is ~0.013% per interval. Higher funding = more profit; negative funding flips strategy direction.
Funding arbitrage scenarios
Bull market positive funding: BTC at $77K, funding 0.04% per 8-hour period (3/day). Position $10K each side. Daily funding income = $10K × 0.04% × 3 = $12. Annualized $4,380 = 43.8% APR. Trading fees over 30 days = $10K × 0.04% × 4 = $16. Net 30-day profit = $360 - $16 = $344. APR ≈ 41.3% net.
Negative funding regime: in bear markets when shorts dominate, funding goes negative. Reverse strategy: short spot (via lending) + long perp = collect funding paid by shorts. Less common in crypto due to spot-borrowing costs (often 5-15% APR), making the math tighter.
Risk and execution checklist
- Before opening basis trade: 1) Verify spot exchange and perp exchange supports same asset with sufficient liquidity. 2) Check funding rate history — single positive reading isn't enough; want 7-day average positive. 3) Calculate margin requirements; over-leverage risks liquidation. 4) Confirm withdrawal/deposit speeds for rebalancing if needed.
- Liquidation risk: maintain perp position with at least 3-5x maintenance margin buffer. A $10K short perp at 10x leverage with $1K margin liquidates if price rises 10%. Use isolated margin and add buffer to survive 30%+ adverse spikes.
Common mistakes to avoid
- Underestimating funding rate volatility. Funding can flip negative quickly (post-news event, FOMC, ETF flows). A trade opened at +0.05% funding may pay -0.03% within days. Monitor daily and exit if funding turns persistently negative.
- Forgetting capital efficiency. Holding $10K spot + $10K perp margin = $20K capital tied up. ROI on capital = profit / total capital, not just one side. The 43% APR figure above is on the perp leg; on full $20K it's 21.5% APR.
Funding rate regime benchmarks
Funding rate annual ranges (BTC perpetuals): bear 2022 average -0.005%/day (-1.8% APR), neutral 2023 +0.01%/day (3.6%), bull 2024 +0.04%/day (14.4%), peak Q4 2024 +0.10%/day (36%), post-ETF launch sustained >0.05%/day (18%+ APR). Sharp spikes to 0.3%+ during euphoria phases.
Best regime for basis trade: persistent positive funding above 0.03% per 8-hour interval, low volatility (reduces liquidation risk), and tight bid-ask on both spot and perp. Coinbase + Binance/OKX/Bybit perp pairs typically offer best liquidity.
Execution templates you can reuse
Standard workflow: 1) Fund spot exchange with USD/USDT, fund perp exchange with USDT margin. 2) Buy spot BTC with full position size. 3) Open short perp with same notional (matching delta). 4) Monitor funding rate daily; close if turns negative for 3+ consecutive periods. 5) Rebalance if perp PnL drifts (position size mismatch).
For execution speed: place spot and perp orders within 30 seconds of each other to minimize directional exposure. If BTC moves 1% between legs, you have unwanted directional position until rebalanced. Limit orders at mid prevent slippage but risk non-execution.
Data hygiene and model maintenance
Daily PnL tracking: log funding received, funding paid (if applicable), trading fees, mark-to-market on each leg. Over 30 days, verify net P&L matches expected (funding income - fees). Discrepancy reveals hidden costs (cross-exchange withdrawal fees, conversion spreads).
Tax records: each funding payment is taxable income (treated as interest in most jurisdictions). Each leg open/close generates capital gains/losses. Maintain trade log with timestamps for accurate <a href="/tax-calculator/">tax calculation</a>.
Pre-trade basis verification
Sanity check: position $10K, funding 0.05%/8hr × 3 = 0.15%/day × 30 days = 4.5% gross. Trading fees 0.04% × 4 = 0.16%. Net 30-day = 4.34% on each side. APR if repeated = 4.34% × 12 = 52%. If calculator shows differently, verify intervals_per_day input (default 3 for 8hr funding; some exchanges use 1-hour intervals = 24/day).
Position verification: spot balance × spot price ≈ perp position notional. Discrepancy >5% indicates unbalanced delta — risk of unintended directional exposure. Rebalance immediately to avoid unintended P&L from price moves.
Authoritative sources
Frequently asked questions
What is perpetual funding arbitrage?
It's a delta-neutral strategy: hold spot crypto + short equal-size perpetual futures. When funding rates are positive (longs pay shorts), the short side collects funding payments while spot and perp price moves cancel out. Annualized returns: 8-50% depending on market conditions. Also called "basis trade" or "cash-and-carry."
How are perpetual funding rates calculated?
Funding rate = premium index + clamp(interest rate − premium index). When perp price trades above spot (positive premium), longs pay shorts; below spot (negative premium), shorts pay longs. Typical interval: every 8 hours. A 0.05% funding rate at 8-hour intervals = 0.15%/day = 54.75% annualized if maintained.
Is perpetual funding arbitrage risk-free?
No. Risks include: (1) liquidation of the perp short if price spikes (margin requirements), (2) funding rate flipping negative (you start paying instead of receiving), (3) counterparty risk (exchange insolvency, withdrawal freezes), (4) execution slippage between spot and perp legs. Maintain 3-5× maintenance margin buffer and monitor daily.
How much capital do I need for funding arbitrage?
Minimum practical size: $5,000-10,000 to make fee economics work. You'll need roughly equal capital on spot exchange (Coinbase, Kraken) and perp exchange (Binance, Bybit, OKX). For $10K notional, expect $10K spot + $1K-2K perp margin (depending on leverage) = $11-12K total capital. APR is calculated on full capital, not just one side.
What happens when funding rates go negative?
Strategy reverses or pauses. With negative funding, your short perp pays funding to longs — net negative carry. Options: (1) close the trade and wait for positive funding regime, (2) reverse strategy (long perp + short spot via borrowing, if borrow costs are lower than negative funding), (3) exit altogether. Persistent negative funding usually accompanies bear markets.
Which exchanges are best for funding arbitrage?
Best combos in 2026: Coinbase Pro (spot) + Bybit/Binance (perp), or Kraken (spot) + OKX (perp). Look for: deep liquidity on both legs, low maker fees (0.02-0.05%), reliable withdrawal/deposit, and 8-hour funding intervals (some exchanges use 1-hour which compounds differently). Avoid exchanges with manipulated/illiquid perps.
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