Margining

Margin is enforced natively inside the exchange engine and verified atomically before any order is accepted. Margining is whole-account (cross): your entire USDX balance is the collateral pool backing every open position. Per-market isolated margin is planned for a later release.

Definitions

Term	Meaning
Notional	position_size × mark_price — the value of the position at the current mark price.
Equity	Account balance + unrealized PnL across all positions.
Initial margin	Collateral required to open or increase a position.
Maintenance margin	Minimum collateral required to keep a position open.

Initial margin

Initial margin is the notional scaled by the market's initial margin rate:

initial_margin = position_size × mark_price × initial_margin_rate

Equivalently, initial_margin_rate = 1 / max_leverage. The engine sums the initial margin required across all positions and rejects an order if your equity cannot cover it.

Leverage

Leverage is a standing per-market setting on your account, not an order parameter. Set it with:

POST /leverage    { "market_id": "BTC-USDX-PERP", "leverage": 10 }

Every subsequent order in that market then requires:

initial_margin = position_size × mark_price / leverage

So raising leverage lowers the margin an order requires, and lowering it raises the margin.

Leverage accepts any whole number from 1 up to the market's effective ceiling — there is no fixed tier set, and the preset buttons an interface offers are its own choice on top of this range. The ceiling is:

max = min(max_leverage, floor(1 / initial_margin_rate))

The market's initial margin rate floors the margin an order can require, and therefore also caps leverage — which means a leverage selection can only make your margin requirement stricter than the market's, never looser. At the ceiling the two formulas above agree. Read the ceiling for a market from GET /markets/{market_id}/risk-params.

You do not have to set leverage before your first order. Left unset, it behaves as the market maximum.

Leverage does not move your liquidation price. That price is set by the maintenance margin rate, which leverage does not touch — POST /orders/preview reports the same projected liquidation price at any leverage. What leverage changes is how much margin a new order consumes, and therefore how much you can open.

Maintenance margin

Each market defines its own maintenance margin rate — a configured fraction of notional, not a value derived from leverage at request time:

maintenance_margin = position_size × mark_price × maintenance_margin_rate

The maintenance margin rate is always less than or equal to the initial margin rate (the engine rejects any configuration where maintenance exceeds initial). A position becomes eligible for liquidation when account equity falls below the total maintenance margin across all positions:

liquidatable when:  equity < Σ maintenance_margin

Rates differ per market, and are still being tuned. An earlier revision of this page said every market ran a flat 2% profile with initial_margin_rate = maintenance_margin_rate. That is no longer true: the listed markets now carry distinct rates, and maintenance is below initial on several of them. Margin rates are per-market configuration and continue to be tuned across release gates. Market Specifications is the authority — it is generated from the configuration the exchange boots from, and it flags any value that is ratified but not yet deployed to the venue.

Why mark price, not last price

All margin calculations use the mark price — an external index price — rather than the last trade on the book. This prevents a single thin-book trade from pushing an account into liquidation.