In All InX's USDT perpetual contracts, the funding fee mechanism is used to keep the contract price close to the spot market price. Here's a complete explanation:
1️⃣ What is the Funding Rate?
Since perpetual contracts have no expiration, the funding rate system is used to balance the price of the contract and the spot market price.
When the funding rate is positive, 👉 longs pay shorts.
When the funding rate is negative, 👉 shorts pay longs.
2️⃣ Funding Fee Collection
📅 Collection Times: 08:00 / 16:00 / 24:00 (GMT+8) every day
💡 You are only charged a funding fee if you hold a position at these times.
✅ If you close your position before the funding fee window, no fee is charged.
Formula:
Funding Fee = Position Value × Funding Rate
Position Value = Contract Quantity × Contract Size × Mark Price
📍 Leverage does not affect the funding fee calculation.
📘 Example:
User holds a long position of 100 BTC contracts
Contract size: 0.001 BTC
Mark price: 8,000 USDT
Funding rate: 0.01%
Funding Fee = 0.001 × 100 × 8000 × 0.01% = 0.08 USDT
3️⃣ How is the Funding Rate Calculated?
The funding rate consists of two parts:
🔸 Interest Rate Component
This is the difference between the interest rates of the base and quote currencies.
Interest Rate (I) = (Quote Interest Rate - Base Interest Rate) / Funding Interval
For USDT contracts, All InX currently uses a fixed interest rate of 0.00% daily
This may be adjusted based on market conditions like the Federal Funds Rate
🔸 Premium/Discount Index
This reflects whether the perpetual contract is trading at a premium or discount relative to the mark price.
Premium Index = [Max(0, Weighted Bid Price – Mark Price) - Max(0, Mark Price – Weighted Ask Price)] / Spot Price + Reasonable Basis
Weighted Bid/Ask Price: Based on cumulative depth (80 contracts for BTC, 800 for other coins)
4️⃣ Final Funding Rate Formula
All InX calculates the Premium Index every minute and takes the time-weighted average every 8 hours. Final funding rate is:
Funding Rate (F) = Premium Index (P) + clamp(Interest Rate (I) - P, +0.05%, -0.05%)
📌 Interpretation:
If (I - P) is within ±0.05%, then F = I
If Premium Index is between -0.04% and 0.06%, Funding Rate will be 0.01% (i.e. the Interest Rate)
5️⃣ Funding Rate Cap
To support high leverage trading, All InX applies funding rate caps:
Absolute cap:
Max Funding Rate = (Initial Margin Rate – Maintenance Margin Rate) × 75%
Example:
If initial margin = 1% and maintenance margin = 0.5%,
Then: Max funding rate = 75% × (1% - 0.5%) = 0.375%Change cap:
The funding rate cannot change more than 75% of the maintenance margin per interval
📬 For more details, refer to the Perpetual Contract Trading Guide or contact our support team anytime.