AUM (Assets Under Management)

For an ETF, the total dollar value of all assets held in the fund. ETF equivalent of market cap.

AUM (Assets Under Management) — For an ETF, the total dollar value of all assets held in the fund. ETF equivalent of market cap.

Key facts

Category
ETF-specific
Definition
For an ETF, the total dollar value of all assets held in the fund. ETF equivalent of market cap.
Live example
/research/stock/SPY
Last updated
2026-06-17

Interpretive bands

< $100M
Small fund. Risk of closure if AUM doesn't grow.
$100M – $1B
Established but not at scale. Slightly wider spreads.
$1B – $10B
Mainstream. Tight spreads, deep liquidity.
> $100B
Mega-fund. SPY, VOO, IVV.

How IndexAlpha uses AUM (Assets Under Management)

AUM is the headline metric on every ETF Fundamentals card. Higher AUM = better tracking, tighter spreads, longer expected fund life.

See it live

The AUM (Assets Under Management) metric shows up on every IndexAlpha research page. See it now on SPY — or research any stock to view its AUM (Assets Under Management).

Related terms

Common questions

What is AUM (Assets Under Management)?

For an ETF, the total dollar value of all assets held in the fund. ETF equivalent of market cap.

How does IndexAlpha use AUM (Assets Under Management)?

AUM is the headline metric on every ETF Fundamentals card. Higher AUM = better tracking, tighter spreads, longer expected fund life.

Sources