Zoomex has released a detailed breakdown of how its perpetual futures contracts calculate funding rates, giving traders a clearer picture of the costs tied to holding positions indefinitely. The exchange offers two types of perpetual contracts—Inverse Perpetual Contracts, collateralized in the base coin, and USDT Perpetual Contracts, denominated in Tether—each subject to the same recurring payment system that keeps contract prices aligned with spot markets.
How the funding rate works
Unlike standard futures, perpetual futures have no expiration date. Traders can hold a position as long as they maintain enough margin. To prevent the contract price from drifting too far from the underlying spot price, Zoomex applies a funding rate—a periodic payment between longs and shorts. When the rate is positive, long position holders pay short holders; when negative, shorts pay longs. The funding fee equals position value multiplied by the funding rate, and payments occur three times daily at 8:00 AM, 4:00 PM, and 12:00 AM UTC.
The two components of the rate
Zoomex derives the funding rate from an Interest Rate (I) and a Premium Index (P). The interest rate uses standard values of 0.06% for the quote currency and 0.03% for the base currency across three daily intervals, yielding 0.01% per funding period. The premium index measures the gap between the perpetual trading price—using Impact Bid and Ask—and the underlying mark price. Every minute, Zoomex calculates these components and applies an 8-hour Time-Weighted Average Price to smooth out volatility.
Clamp function stops extreme swings
The final funding rate formula is F = P + clamp(I - P, -0.05%, +0.05%). The clamp function acts as a dampener, capping the deviation between the interest rate and the premium index. This prevents the funding rate from spiking too high or low during sudden market moves, keeping payments predictable for traders on both sides of the trade.
Dual-price mechanism shields liquidations
Zoomex uses a Dual-Price Mechanism that separates the mark price from the last traded price. The mark price is derived from a global spot price index across major exchanges, plus a decaying funding basis rate. Liquidations and unrealized profit-and-loss calculations rely on the mark price, not the last traded price, reducing the risk of manipulation. If a position can't be liquidated at the bankruptcy price, the exchange's insurance fund covers the loss.
Zoomex's explanation gives perpetual futures users a clearer understanding of when they'll pay—or collect—funding fees, and how the system guards against extreme pricing disconnects.
