The square-root law says the price impact of an order scales with the square root of its size relative to daily volume. It is the standard rule for estimating what a large order will cost in impact.
Impact ≈ a constant × volatility × √(order size ÷ daily volume). The √ means impact grows slower than size, but it never stops growing — there is no free large order.
Because impact is sub-linear, splitting a big order into smaller pieces across venues and over time lowers the total paid. The law is why size, not just venue, drives execution cost.
EnsoTrade prices a large order against live order books across venues — which venues to use, what size each piece should be, and whether to rest an order or cross the spread. It is independent measurement, not execution: your own desk or execution partner keeps placing the orders on its own accounts, and we never touch custody, keys or funds. Before a window we price it at your real clip size on the venues you can use; after a window we score the fill with full workings. We quote no price or saving until you give your real clip size and fee stack — then the number is yours to check.
Price an order before you trade and score the fill after, on live multi-venue order books. We never touch custody, keys or orders — the independence is the point.
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