ETF liquidity
Why an ETF's tradability depends on its underlying assets, not just its own volume.
An ETF has two layers of liquidity: the visible layer (its own trading volume and quoted spread) and the deeper layer (the liquidity of what it holds). Because APs can create and redeem shares, a low-volume ETF holding liquid large-cap stocks can still absorb large orders near fair value.
That said, screen liquidity still matters for everyday investors: funds with tiny volume tend to quote wider bid/ask spreads, and market orders in them can execute at poor prices. Assets under management, average volume, and typical spread together give a fuller picture — this site shows volume and AUM on every fund page.
Practical habits: prefer limit orders, avoid the market open and close, and be extra careful with funds holding assets that trade in other time zones.