Definition
Margin level
Margin level is the percentage (equity ÷ used margin × 100) a broker uses to decide when an account is too stretched to keep its positions open.
It falls when equity drops (losing trades) or when used margin rises (more or larger positions). A high percentage means plenty of headroom; a low one means the collateral is nearly exhausted.
Below the broker's stop-out level, positions are force-closed automatically.