Perpetual future (perp)
A futures contract with no expiry date, kept near the spot price by periodic payments between long and short holders.
A perpetual future, or perp, tracks the price of an underlying asset like a futures contract but never expires. A trader can hold the position for as long as the margin in the account covers its losses. Instead of a settlement date, the contract uses a funding rate to pull its price back toward the spot price.
On our site, a perp appears as its own quote beside the spot market for the same asset. Compare the two to see the basis, and check the funding rate and open interest before reading the perp price as a signal.
Traders care because perps are often the most liquid venue for an asset, and leverage makes them sensitive to liquidations.
Worked example (illustrative numbers, not real data): spot is 50,000 and the perp trades at 50,100. A trader is long 2 units, a notional of about 100,200. Funding is 0.01 percent every 8 hours and longs are paying, so the trader pays about 10 dollars per interval, or roughly 30 dollars a day.