Perp Arbitrage Calculator
When a perpetual future trades at a premium to spot, you can short the perp, long spot, and profit as the premium converges— plus any funding you net while holding. This estimates the P&L after fees.
Short the perp (trading above spot), long spot in equal size, and profit as the premium converges toward zero. Four fills total; funding is what you net while holding.
Net profit
$17.00
+0.34% on capital
Worked examples
$5,000 per leg, 0.04% fee per fill — from the calculator above:
Modest premium closes
0.5% → 0.0% · no funding
+$17
+0.34%
Half-a-percent premium converging clears four fills — modestly.
Wide premium + funding
1.0% → 0.1% · +0.1% funding
+$42
+0.84%
A fat premium plus positive funding is the ideal setup.
Thin premium
0.15% → 0.0% · no funding
−$0.50
−0.01%
Too small to beat fees — wait for a wider premium.
The honest caveats
Perpetuals are tethered to spot by the funding mechanism, so a premium usually doesrevert — that's the edge. But “usually” isn't “now”: the premium can widen first, showing an unrealized loss on the short leg, and a sharp spot rally can liquidate an under-margined short before convergence arrives. You also carry each exchange's solvency risk. It's a real, delta-neutral setup — but sizing and margin buffer are what keep it from blowing up.
Closely related is collecting funding continuously rather than betting on convergence — see the funding rate arbitrage calculator.
FAQ
What is perp (basis) arbitrage?
When a perpetual future trades above (or below) spot, you take offsetting positions — short the richer leg, long the cheaper — so you're delta-neutral, and you profit as the gap (basis/premium) converges.
Is it risk-free?
No. The premium can widen before it converges (unrealized loss), the short leg can be liquidated on a spike if under-margined, and you carry exchange risk. It removes directional risk, not all risk.
How is this different from funding-rate arbitrage?
Funding arb collects the recurring funding payment while staying delta-neutral. Convergence arb bets on the price gap between perp and spot closing. They often overlap — a rich perp both pays funding and tends to converge.
Estimates only, ignoring slippage, margin calls, and mid-trade drawdown. Crypto is volatile and not FDIC-insured. Not financial advice.