Mark Price vs Last Price vs Index Price: Why Perps Liquidate Where They Do

You get liquidated, open the chart, and the candle never touched your liquidation price. Nothing is broken. Your position was tracking mark price, while your chart was showing last price, and in fast markets the two can disagree by enough to matter. Every perpetual futures market actually runs on three prices at once: last price, mark price, and index price. Each has a different job, and knowing which one controls what is the difference between managing risk precisely and being surprised at the worst moment. This guide explains all three in plain language, with the exact scenario that catches most traders.

The short version: last price is the most recent trade, mark price is the fair value your liquidation and PnL are calculated on, and index price (called the oracle price on Hyperliquid) is the weighted median of major-exchange prices that anchors everything. Charts show last price. Liquidation engines watch mark price. If you only remember one thing, remember that.

The Three Prices, Explained Simply

Last price is exactly what it sounds like: the price of the most recent trade matched in the order book. Every candle on your chart is built from last prices. It is the most immediate number, and also the most fragile, because on a thin book a single large order can push it far from where the rest of the world prices the asset.

Index price is the anchor. It is a weighted median of the asset's price across several major exchanges at once, and on Hyperliquid, the network that powers Perpmate, it is called the oracle price. Hyperliquid's validators build it from a weighted median of prices on venues like Binance, OKX, Bybit, Gate, and MEXC, and it refreshes every few seconds. Think of it as the market's consensus of what the asset is actually worth right now, independent of anything happening on one venue. Manipulating it would require moving prices everywhere simultaneously.

Mark price is the exchange's estimate of the contract's fair value, and it is the number that matters most for your account. Rather than trusting any single source, Hyperliquid builds it by taking the median of a few inputs at once: the oracle price adjusted by a smoothed basis, the median of Hyperliquid's own best bid, best ask, and last trade, and the median of perp prices on major exchanges. Blending these means a sudden one-second spike on any single input gets averaged away, so mark price moves like a steadier version of reality.

If you have read our guide on what perpetual futures are, you know perps have no expiry to force them back to spot. The oracle price and funding rates do that job continuously, and mark price is where the mechanism becomes visible in your positions.

What Each Price Controls

The division of labor is consistent across serious platforms, including Perpmate:

• Order fills happen at last price levels. When you buy or sell, you trade against the order book, so your entries and exits are last-price events.
• Unrealized PnL and margin health are calculated on mark price. The floating profit or loss you see on an open position follows mark, not last.
• Liquidations trigger on mark price. Your liquidation level is compared to mark price, tick by tick. How liquidation works covers the margin math behind that level.
• Funding payments are derived from the gap between the perp's price and the oracle price. When the perp runs hot above the oracle, longs pay shorts, hourly on Hyperliquid-based platforms like Perpmate and every 8 hours on most centralized exchanges.

The Scenario That Catches Everyone

Here is the situation that generates most "I was liquidated early" complaints, with numbers.

Say BTC sits at $100,000 across major exchanges, so the oracle price is $100,000. The market is euphoric and the perp trades at $101,000, a 1% premium. You are long at 20x leverage, and your liquidation price is $99,500 on mark. On your chart, price is comfortably at $101,000 and your liquidation level looks over a thousand dollars away.

Now the euphoria cools. The oracle barely moves, drifting to $99,800, but the leveraged crowd unwinds and the premium collapses from 1% to zero. Last price slides from $101,000 to $99,800, a modest red candle. Mark price, anchored to the oracle, went from roughly $100,900 to $99,800 as well, but along the way the smoothed premium compression pulled it through $99,500. Your position is liquidated. The chart never printed a violent move, and traders watching only candles are left confused.

The reverse also happens and it saves you. A whale dumps into a thin book and last price wicks down 3% for two seconds on one venue. If liquidations ran on last price, that wick would have wiped out every long in its path and the forced selling would have cascaded further. Because mark price is anchored to a weighted median of multiple exchanges and smoothed over a window, the wick passes and positions survive. This wick protection is the entire reason mark price exists.

Why This Design Protects You

It can feel unfair to be liquidated on a price your chart never showed, but the alternative is far worse. Last price on any single exchange is the easiest number in crypto to manipulate: find a thin order book, push it with one large order, harvest the liquidations, and let the price snap back. Early perpetual markets suffered exactly these attacks.

Mark price makes the attack economics terrible. To move it, you would need to move the prices on several major exchanges that feed the oracle at once, and hold them there long enough to beat the smoothing window. The capital required usually exceeds anything the attacker could harvest. The occasional premium-compression liquidation is the cost of that protection, and it is a cost you can manage once you know it exists.

How to Trade With Three Prices in Mind

The practical adjustments are small but they compound:

1. Manage risk on mark price, not the chart. Your platform shows the mark price and your liquidation level side by side. That pair is your real risk dashboard; candles are just where your fills happen.
2. Leave room for premium swings. If the perp is trading at a strong premium while you are long, understand that the premium itself is part of your cushion and it can vanish without spot moving. Cutting leverage is the simplest fix. Our position sizing guide shows how to size so a 1-2% adverse move never threatens the account.
3. Remember your stops trigger on mark price. On Hyperliquid, which powers Perpmate, stop-loss and take-profit orders fire on mark price, not the last trade. That means a single-venue wick will not trigger them, but it also means you should place them relative to mark price rather than the raw candle. Our guide on stop-losses and take-profits covers placement in detail.
4. Watch the premium as a sentiment gauge. A perp trading persistently above the oracle with rising funding means longs are crowded. That is exactly when premium-compression moves like the scenario above become likely, and when reading open interest alongside the premium tells you how loaded the market is.

The Bottom Line

Last price is where you trade, mark price is where you live or die, and the index or oracle price is the anchor keeping both honest. The trader who watches only candles is managing a position with the wrong number and will eventually be surprised by a liquidation the chart cannot explain. The fix costs nothing: know your mark price, know your liquidation level, size positions so the gap between them stays wide, and let the smoothing that occasionally works against you keep protecting you from every wick it silently absorbs.

For the full picture of how these prices feed the margin math, read how liquidation works next, or start trading with the prices visible on Perpmate, where the mark and oracle prices are shown for every market.