Market intelligence
How Do S&P 500, Nasdaq-100, and Dow 30 Differ?
The S&P 500 and Nasdaq-100 use market-cap-based weighting rules; the Dow is price-weighted. Their constituent counts and methodologies differ.
What problem does this solve?
You want to understand why market views produce different rankings and contributions.
Quick answer
The S&P 500 uses float-adjusted market-cap weighting, the Nasdaq-100 uses modified market-cap weighting, and the Dow 30 is price-weighted.
Steps
- Use this as an index-methodology comparison, not instructions for switching desktop markets.
- The current Market Watch 360 app follows only an IVV-weighted S&P 500 basket.
- The website's Nasdaq-100 and Dow hero art is static illustration of planned markets, not working app views.
What you should see
You can compare the three benchmark methods without assuming all three are implemented in the Windows application.
If it still doesn't work
Use the linked Learn comparison and official methodologies when a particular constituent or weight appears surprising.
Screenshot or video
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