BYDFi liquidation distance from fair price: the advanced BTC table at 20x, 50x and 100x

Advanced tier, built on BYDFi's BTC_USDT perpetual at about 4:00 PM ET on Nov 3, 2026: last 77,836.7, fair 77,836.8, index 77,856.6, funding 0.01% on an 8 hour cycle with the next settlement about 3 hours out. The 24h range was 76,351.8 to 77,925.2. BYDFi's contract detail listed a first-tier maintenance rate of 0.1%, max leverage 500x, and fees of 0.02% maker and 0.06% taker.

How BYDFi builds fair price

Fair price = median of three values: Price 1 = index x [1 + funding rate x (hours to next funding / 8)] Price 2 = index + 30 minute moving average of the basis, where basis = (best bid + best ask)/2 - index, sampled every minute Price 3 = last traded price In extreme conditions, when spot and mark deviate sharply, BYDFi uses Price 2 directly.

Snapshot check: Price 1 = 77,856.6 x (1 + 0.0001 x 3/8) = 77,859.52. Price 3 = 77,836.7. Fair = 77,836.8 sits between them, so it is Price 2. Implied basis = 77,836.8 - 77,856.6 = -19.8, about -0.025% versus index.

A 30 minute window sampled each minute is slow by design. A single print cannot drag it, which is the point.

The table

Long BTC at 77,836.7, isolated, simplified liquidation = entry x (1 - 1/leverage + 0.001), before fees. Distance measured from fair 77,836.8.

Now compare with the day. High minus low = 77,925.2 - 76,351.8 = 1,573.4, about 2.02% of fair. At 50x the buffer was smaller than the day's range. At 100x it was less than half of it.

Fees eat high-leverage margin

At 0.06% taker in and out, a round trip costs 0.12% of notional. At 100x your margin is 1% of notional, so the round trip is 12% of your margin. At 50x it is 6%. At 20x, 2.4%. Fees are charged on notional, so the higher the leverage, the bigger the bite out of your margin.

Stops, trigger types and price protection

BYDFi trigger orders can fire on last, fair or index price. A triggered stop executes as a market order, so the fill can differ from the trigger in fast markets.

At 100x with liquidation at 77,136.2, a last-price stop at 77,200 sits 63.8 above the line. If a premium fades and fair drops faster than last, fair reaches 77,136.2 first and liquidation takes over. A fair-price stop removes that particular race, but it still fills at market.

Price protection is the other switch. When enabled, a TP/SL that hits its trigger is rejected if the gap between latest price and fair price exceeds that pair's threshold. It shields you from wick exits; it can also leave you without an exit during a genuine dislocation.

Mistakes worth naming

• Measuring buffer from the candle instead of fair.
• Picking leverage first and checking the day's range after.
• Ignoring the fee share of margin at 50x and above.
• Placing a last-price stop a few dollars above liquidation.
• Enabling price protection and forgetting it exists.

FAQ

Q: When exactly does BYDFi liquidate? A: When fair price reaches the liquidation price and the maintenance margin ratio hits 100%.

Q: Why is fair below index today? A: The perp book's midpoint has averaged under index over the last 30 minutes, so the basis is negative.

Q: Do alts show the same pattern? A: At the same time ETH_USDT read last 2,289.38, fair 2,289.38, index 2,290.48, and SOL_USDT read last 93.54, fair 93.54, index 93.57. Same small discount.

Challenge for your next BYDFi entry: write your fair-price distance to liquidation next to the day's high-low range before you click. If the first number is smaller, change the size or the leverage, not the stop.