Perpetual futures

Reading time ~5 min · Last updated 2026-07-17

All four BitBreakout markets — BTC-PERP, ETH-PERP, SOL-PERP and XRP-PERP — are perpetual futures ("perps"). Invented for Bitcoin in 2016, perps are now where the overwhelming majority of crypto trading volume happens, dwarfing spot. The suffix -PERP is what tells you the contract type.

The problem with expiry

A traditional futures contract expires. A trader who wants to stay positioned must close the expiring contract and reopen in the next one ("rolling"), paying fees and spread each time, and juggling several contracts (March, June, September…) with slightly different prices. The perpetual removes all of that: one contract per market, held for as long as you like — a minute or a year.

The tethering problem

Expiry did one important job: it forced the futures price to converge with the real (spot) price at settlement. Remove expiry and nothing obviously anchors the contract to reality — a perp could in principle drift far away from the actual price of Bitcoin. Perps solve this with a clever mechanism called the funding rate: periodic payments between longs and shorts that nudge the perp price back toward spot. It is important enough to get its own article.

Three prices, not one

In the terminal you will notice a market has several slightly different prices at once. Each has a job:

PriceWhat it isWhat it's used for
Last priceThe most recent trade on the tapeWhat the chart draws
Index priceA reference of the underlying spot priceThe anchor that funding pushes the perp toward
Mark priceA smoothed, manipulation-resistant fair valueValuing your open positions and triggering liquidations

Positions are valued at the mark price, not the last traded price. This is deliberate: a single outlier trade can spike the last price for a moment, and no one should be liquidated because of one weird print. If your position PnL briefly disagrees with the chart, mark-vs-last is almost always why.

On BitBreakout

Prices come from live market data streamed from a reference exchange. Your orders are matched against this live order book inside the simulator — they never touch the real market. The behaviour (funding, marking, liquidation) mirrors a real perp venue so the skills transfer.

Why perps dominate crypto

  • Simplicity — one contract per market; no expiry calendar, no rolling.
  • Leverage — capital efficiency for both speculation and hedging.
  • Two-sided — shorting is as easy as longing, which spot never made easy.
  • 24/7 — like crypto itself, perps never close. Volatility does not wait for business hours.
Key takeaway

A perpetual is a futures contract with no expiry, kept honest by funding payments and valued at a smoothed mark price. Understand funding and margin and you understand perps.