Intrinio provides end of day index prices in the US Fundamentals & Stock Prices data feed. These resources will help you access these data points:
Pulling index prices via API looks like this:
Pulling via Excel looks like this:
Please note that prior to 12/15/17, we had coverage for NYSE Composite, S&P 100 Index, Russell 2000® Price Index, French CAC 40 Index, Hong Kong Hang Seng Index, and German DAX Composite, but our index coverage has been changed to include S&P 500, Dow Jones Industrial Average, Dow Jones Composite Average, Dow Jones Transportation Average, Dow Jones Utility Average, NASDAQ 100 Index, and NASDAQ Composite Index.