Perpetual Future
Also known as: Perp, Perpetual swap
Crypto's native derivative: a future that never expires, tethered to spot by a funding rate.
1 · SnapshotThe one idea to remember
2 · BeginnerWhat is it, really?
A perpetual future is crypto's great financial invention: a futures contract with no expiry date. You can hold a leveraged long or short forever — no rolling, no delivery, no calendar.
But a future needs something to tie it to the real price. Perps solve this with the funding rate: every few hours, whichever side of the market is more crowded pays the other. Perp trading above spot (longs greedy)? Longs pay shorts — an incentive that pulls the price back down toward spot. Below spot? Shorts pay longs.
Perps now do several times the volume of spot crypto — they are where crypto's leverage, speculation and price discovery actually live. With leverage up to 100x on offer, they're also where accounts go to die: mass liquidations of overleveraged perp positions are the mechanism behind crypto's trademark cascade crashes.
Point at a line to pick it out from the others.
a paymentonly if a condition is met
A future with no expiry needs something to hold it near spot. That something is a payment from one side of the market to the other, several times a day.
Opening a position
- Longs → The venue Leverage of many times the deposit is routinely available, which is why liquidation is the normal ending rather than the exceptional one.
Every few hours
- Longs → Shorts Paid directly from longs to shorts. The venue takes none of it; it exists purely to pull the contract back toward spot.
- Shorts → Longs The same mechanism in reverse. A crowded position pays to stay crowded.
If the margin runs out
- The venue → Longs Automatic, without a telephone call, and at whatever the book offers. In a fast move the liquidations themselves become the move.
If the loss exceeds the margin
- The venue → Shorts When a liquidation cannot be filled, some venues close profitable opposite positions to balance the books. A winning trade can be closed for you.
- Asset class
- Digital assets
- Instrument type
- Perpetual futures contract
- Traded
- Crypto derivatives exchanges, 24/7
- Typical users
- Traders, market makers, hedgers
Which risks decide the outcome
Not how risky this is, and not a rating — there is deliberately no total. It says which of five failure modes drives what happens here, in the same order on all 129 products so they can be compared. This publication's own reading; see the notice below.
- Marketdecides it
- Creditbarely applies
- Liquiditymatters
- Fundingdecides it
- Operationalmatters
What decides it here. Funding is paid between traders several times a day, and liquidation is the normal ending rather than the exceptional one. In a fast move the liquidations become the move.
3 · IntermediateHow it works in practice
Mechanics
- Funding (typically every 8h, or continuous): rate ≈ premium of perp over a spot index, plus a small fixed interest component. Annualised it can hit ±100% in manias.
- Mark price: liquidations trigger off a blended index (not the exchange's own last trade) to resist manipulation.
- Liquidation engine: positions below maintenance margin are force-closed; insurance funds absorb slippage; in extremes, auto-deleveraging (ADL) claws back profits from winners — a mutualisation TradFi doesn't have.
- Collateral: stablecoin-margined (linear P&L) or coin-margined ("inverse" contracts, P&L in the crypto itself — convexity quirks included).
The cash-and-carry trade
Persistent positive funding = shorts get paid. The classic "basis trade": buy spot, short the perp, collect funding — crypto's native yield strategy, at times printing double-digit annualised returns, with exchange-credit risk as the true price (ask anyone who ran it on FTX).
Funding as sentiment
Funding across venues is the cleanest live leverage gauge: extreme positive funding precedes long-squeezes; negative funding marks capitulations. Every crypto dashboard worth reading plots it.
4 · AdvancedPricing & valuation
Pricing: an anchored deviation process
Arbitrage bounds the perp-spot gap by funding expectations: fair perp premium over the next funding interval ≈ expected funding payment. Formally, with funding \(f_t\) proportional to premium \(p_t = (F_t - S_t)/S_t\):
What the symbols mean
- ta point in time
- Ean expected value
The design mimics an overnight-indexed rolling future; funding is economically the implied repo/borrow spread of the crypto world, and the perp basis complex (perp vs. dated CME futures vs. spot ETF) now arbitrages into a coherent term structure.
Liquidation cascade dynamics
Leverage + mark-price mechanics create reflexivity: price drop → liquidations → forced selling → further drops. Cascade models resemble fire-sale networks; open interest, funding, and liquidation heatmaps (strike-clustered stop levels) are the monitoring stack. ADL and insurance-fund adequacy determine who ultimately eats gap risk — read the exchange's waterfall like a CCP rulebook, because it is one, minus the regulation.
Inverse-contract convexity
Coin-margined perps settle P&L in the volatile asset itself: a short position's margin gains value exactly when needed (negative correlation), longs suffer the reverse — quanto-like convexity that materially changes optimal hedge ratios (\(1/S\) weighting of position sizes).
TradFi absorption
The funding-rate mechanism is being studied and cloned for 24/7 tokenised markets; perps stand as a genuine financial-engineering innovation from crypto — an expiry-free derivative held together by incentive design rather than delivery.
The formulas above are standard textbook formulations, simplified for teaching. They explain the mechanism — they are not a valuation tool, and they will not reproduce a dealer’s price.
5 · Desk notesHow practitioners think about it
Now say it back
Close the page and give Perpetual Future in four sentences. It takes a minute and it is the only way to find out whether reading it was enough.
- Who wants what — two parties wanted opposite things badly enough to write it down.
- What the contract obliges, and when — not the payoff; the obligation.
- Where the money comes from — name the source, or you have described a hope.
- What makes it lose — the ordinary way, not the dramatic one.
Put Perpetual Future beside any other instrument →
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