Both the VTI and VOO ETFs offer exposure to the US equity markets with a low Management Expense Ratio of 0.03%. The VTI provides investors with broader exposure to stocks across the size spectrum in the US equity market. The VOO is focused exclusively on the 500 largest stocks by market cap. Depending on whether you are aiming for breadth or whether you want to gain exposure to the biggest movers and shakers in the market, the VTI or VOO may be suitable for you, respectively.