[Beginner] How margin actually works on Bitunix futures: 500 USDT, four leverage settings, four liquidation prices

[Beginner guide] The most common first-week mistake on futures is treating the leverage number as a "how bullish am I" dial. On Bitunix it is really a "how close is my liquidation price" dial. Here is how margin actually works, step by step, using the numbers from Bitunix's own help center.

The image is the live Bitunix BTCUSDT perpetual page as it loads logged out this morning. Look at the top of the order form: the margin mode button reads Cross and leverage reads 10X. That is what you start with unless you change it, which is why this guide starts there. The Margin box at the bottom right is where Margin Rate and Maintenance Margin show once you hold a position.

1. Initial margin is what you put up to open the trade.

Margin x leverage = position size (notional). 500 USDT at 10x controls a 5,000 USDT BTC position. The 500 is the only money this position can lose in isolated mode.

1. Maintenance margin is the floor you must stay above.

Bitunix defines it as open price x size x maintenance margin rate (MMR). Its liquidation help article uses an MMR of 0.5% for BTC. On a 5,000 USDT position that is 5,000 x 0.005 = 25 USDT.

1. Available margin moves with your PnL.

Your 500 USDT shrinks as the trade goes against you. When what is left drops below the 25 USDT maintenance margin, Bitunix force-liquidates the position.

1. So leverage decides how much room you have.

Same BTC long, entry 100,000, same 500 USDT isolated margin, MMR 0.5%, before fees and funding:

• 10x: size 5,000, maintenance 25, liquidation 100,000 x (1 - 475/5,000) = 90,500 (a 9.5% drop)
• 20x: size 10,000, maintenance 50, liquidation 100,000 x (1 - 450/10,000) = 95,500 (4.5%)
• 50x: size 25,000, maintenance 125, liquidation 100,000 x (1 - 375/25,000) = 98,500 (1.5%)
• 100x: size 50,000, maintenance 250, liquidation 100,000 x (1 - 250/50,000) = 99,500 (0.5%)

Your money at risk is 500 USDT in every row. The only thing leverage changed is how small a move it takes to lose it.

1. Isolated vs cross changes which money backs the trade.

Isolated: only the margin you assigned to that position. If it is liquidated, the rest of your futures balance is untouched. Cross: every position under the same margin asset shares one balance. Same 10x BTC long, but now the whole 1,000 USDT account backs it: 100,000 x (1 - (1,000 - 25)/5,000) = 80,500. More room, but if it does get liquidated you can lose the full 1,000, not 500. (Simplified: one position open, no fees or funding.)

1. Pick the mode before you trade.

Bitunix will not let you switch between isolated and cross while you have an open position or a pending order on that pair. Close or cancel first.

1. The leverage cap is not a suggestion.

Bitunix's public market data lists max leverage of 200x on BTCUSDT and ETHUSDT, 100x on SOLUSDT and XRPUSDT, and 75x on DOGEUSDT, with 10x as the default. Bigger positions also move into higher maintenance-margin tiers, which raises the MMR and lowers the leverage you can set, so the math above gets tighter as size grows. In isolated mode each direction of each contract is tiered separately; in cross, all directions of a contract count together.

Before your first futures order, check:

• Margin mode set (isolated if you are still learning)
• Leverage chosen from the liquidation price you can live with, not the other way round
• Liquidation price on the order preview noted
• A stop-loss above that price for a long, below it for a short (Bitunix's own help article suggests placing one before liquidation)
• Fees and funding remembered, since both pull the real liquidation price a little closer than the clean math