Perp MechanicsA clearer view of derivatives.Understand the mechanics. Model the outcomes.
Model perpetual futures P&L, funding, basis changes and spot-perpetual hedges using your own hypothetical prices, rates and isolated-margin assumptions.
Linear & inverse contracts
Funding · basis · isolated margin
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After funding, fees & modeled closure
61,020.00 USD capital employed
Initial hedge ratio: 100.00%
Remaining hedge ratio: 100.00%
BTC spot and mark move together; percentage basis stays fixed. Red diamond points include a rejected or liquidated leg. Shocks beyond supported price bounds are omitted.
Projected close at the horizon, or earlier modeled liquidation. Capital transfers are not costs. Net includes only modeled costs; borrowing, financing, taxes, transfers, opportunity costs and liquidity constraints are excluded. Fully quantity-matched spot long / linear short. Return on initial capital: 0.60%.
custom fee: 0.0400% · 20.00 USD
Execution drag: 0.00 USD
custom fee: 0.0400% · 22.00 USD
Execution drag: 0.00 USD
Reference-price P&L: 5,000.00 USD · P&L after execution, before fees and funding: 5,000.00 USD. All leg amounts are in USD.
custom fee: 0.0400% · 20.20 USD
Execution drag: 0.00 USD
custom fee: 0.0400% · 22.04 USD
Execution drag: 0.00 USD
Reference-price P&L: -4,600.00 USD · P&L after execution, before fees and funding: -4,600.00 USD. All leg amounts are in USD.
Exposure offset = 1 − |net units| / gross units. Basis attribution is for surviving linear legs. Perpetuals have no expiry and no guaranteed convergence.
Spot gains do not replenish isolated perpetual collateral. Basis widening, funding reversals and price gaps can close a hedge’s derivative leg.
Flat scenario · 72 hours · Cash & carry. Results are conditional on this deterministic scenario. Spot and other isolated accounts cannot rescue the selected leg.
Leg 2 · short · perp-1
Absolute account reserve, not a fee or percentage. Planner inputs are session-only; saved analyses and JSON are unchanged.
Boundary: 10,120.2 USD
Equality is admissible at the mathematical boundary.
Forward-verified collateral: 10,120.2 USD
Additional collateral required: 0 USD
Minimum planned margin surplus: 5,202.46 USD
Current allocated collateral: 11,000 USD
Current collateral and size already satisfy the plan.
Entry
Initial-margin entry requirement (including opening fee and entry execution drag).
Mark: 50,500 USD
Planned cumulative funding: 0 USD
Planned margin surplus here: 9,827.3 USD
Current position: opens and survives modeled checkpoints.
Quantity boundary: 1.08693504080947
At or below this boundary; equality is admissible.
Risk-derived limit: initial margin · Entry.
Verified admissible quantity: 1.08693504080947
Effective underlying units: 1.086935041 BTC
Entry notional: 54,890.21956 USD
Required reduction: 0 quantity (0%)
Minimum size-plan surplus: 5,654.736072 USD
A smaller proposed size means a different initial position under the same scenario, not a reduction midway through a trade. The contract multiplier stays fixed.
Current: 4.590909091×
At verified maximum initial size: 4.99001996×
Entry notional / allocated collateral. This maximum is conditional on the chosen scenario, collateral, reserve and entry requirements.
The existing leverage input controls initial margin. Changing it alone does not improve liquidation resilience at fixed size and collateral. Additional reserve is not added to initial margin.
Entry eligibility is checked separately from the scenario hour-zero mark. Planning includes all observations and pre-/post-funding checks through the horizon. Survival is established only at modeled checkpoints, not between observations. Mathematical boundaries are not exchange guarantees.
Candidates retain full precision and must survive the forward engine. Zero reserve still requires strictly positive surplus. Positive-reserve equality is allowed. Reserve verification permits only scale-aware floating-point error (collateral-plan tolerance: 1.50e-9 USD).
One linear perpetual, optionally one spot long in the same underlying and quote currency. Prices stay at the entered scenario levels from hour zero. These are conditional closing calculations, not forecasts of price appreciation or basis convergence.
Total return over 72 hours, not annualized. Initial capital denominator: 61,020 USD, comprising spot purchase cost plus its opening fee and allocated perpetual collateral, conditional on all required legs opening. The target input is session-only and is not included in saved analyses or JSON.
≈ -0.06367412785 % / 8 hours
Exact economic threshold verified through closing under the configured isolated margin.
Economic net P&L meets or exceeds the target at or above this threshold, conditional on surviving to close. Other candidates require their own margin check.
≈ -0.06367412785 % / 8 hours
Exact economic threshold verified through closing under the configured isolated margin.
Economic net P&L meets or exceeds the target at or above this threshold, conditional on surviving to close. Other candidates require their own margin check.
≈ 0 hours
0 complete funding payments · search limit 8,760 hours
Already reached at hour zero, after transaction fees and execution drag.
≈ 55,465.53277 USD perpetual mark
Basis: ≈ 465.5327664 USD (0.8464232116% of scenario spot)
Threshold minus currently assumed exit basis: +365.5327664 USD
Only a fully matched spot long / perpetual short qualifies. The candidate mark applies from hour zero and changes funding notional, exit fills, closing fees, execution drag and margin requirements.
Economic basis threshold verified through closing. This is not a safe margin limit.
Economic net P&L meets or exceeds the target at or below this threshold, conditional on surviving to close. Other candidates require their own margin check.
Effective opening and closing fees and both execution drags are included. Funding settles only at complete intervals, without compounding. Spot gains cannot replenish isolated collateral. Feasibility uses unrounded candidates and the chronological engine; displayed thresholds are approximate. A blocked exact threshold does not establish that every profitable scenario is infeasible.
Linear contracts settle price differences in the quote currency. Inverse contracts use reciprocal prices and settle in the underlying coin. Coin profit and its USD value are different quantities. Learn how perpetual futures work →
For a single calculation, choose from the funding, P&L and liquidation calculators.
Positive funding transfers value from longs to shorts; negative funding reverses it. The interval, mark notional and settlement currency determine each modeled payment. Estimate payments with the Funding Rate Calculator →
Long spot and short perpetuals can offset directional exposure. Basis movement, funding and fees still affect returns, and isolated margin can fail while the combined strategy gains. Understand futures basis and convergence →
Read the model assumptions and supported scenarios before interpreting results.