what is the best returning index all time

The S&P 500 (GSPC) has had the highest return by a major index, returning 31,649.2%.

ASSET DATE % RETURN
the S&P 500 (GSPC)
12/30/1927 - 5/6/2025
31,649.21%
the Dow Jones Industrial Average (DJI)
1/2/1950 - 5/6/2025
20,376.95%
the Nasdaq Composite (IXIC)
2/5/1971 - 5/6/2025
17,589.66%