What is an ETF's indicative value (iNAV/IOPV)?

Many ETFs have an indicative intraday value (often called iNAV or IOPV) that estimates the value of the underlying holdings during the trading day.

It can be helpful as a reference point to understand whether the ETF is trading at a premium or discount. But the accuracy depends on how easy it is to price the underlying assets in real time.

In markets where underlying assets don't trade continuously (some bonds or foreign markets), the indicative value can lag or be less precise. That's one reason premiums/discounts and spreads can be larger for certain ETFs.