Seven US stock indexes: the S&P 500, S&P MidCap 400 and S&P SmallCap 600, the Nasdaq-100, the Russell 1000 and Russell 2000, and the Dow Jones Industrial Average.
Every constituent list is a full-replication tracking fund's own disclosed holdings, taken either from an SEC Form N-PORT filing or from the holdings file the fund publishes daily. We hold no index-provider licence and need none: a fund that replicates an index in full holds the index, and it files what it holds. Each answer names the fund and the date it came from.
A list is only published once a fund's filing reaches us whole. A filing that arrived narrowed is stored but never published, because a partial list would read as an index that had shrunk. Rows the fund reported that could not be matched to a company we track are listed under the fund's own name rather than dropped, for the same reason.
GetIndexComposition
Returns one index's current constituent list, heaviest first, with each company's share of the index and the tracking fund's position in it. The answer opens with the provenance sentence: which fund, which filing or holdings file, and which date. Fund shares and fund value size the fund's position, never the company, so a reader cannot mistake a fund's stake for a company's share count or market value. Accepts an index by slug or by name, so sp-500, S&P 500 and SPX all name the same list; a spelling that could name two indexes, such as russell, is refused rather than resolved to one of them.
Parameters: index (required: slug or name, for example sp-500, S&P 500, nasdaq-100, Russell 2000), maxResults (default 100, max 500), offset (default 0, for paging through a full list).
Ask: "What companies are in the S&P 500 right now, and what are the ten biggest weights?"
Returns:
## S&P 500 constituents
504 companies. As held by iShares Core S&P 500 ETF (IVV) daily basket on 19 Aug 2026, from the holdings file the fund publishes on its own site (retrieved 20 Aug 2026).
Weight is the company's share of the index. Fund shares and fund value size the tracking fund's position, never the company.
2 of these rows could not be matched to a tracked company, because filers mask the identifier for some foreign-domiciled issuers. They are listed under the name the fund reported.
| # | Ticker | Company | Weight | Fund shares | Fund value |
|---:|---|---|---:|---:|---:|
| 1 | NVDA | Nvidia Corp | 7.95% | 327,009,346 | 71,144,153,316 |
| 2 | AAPL | Apple Inc. | 7.02% | 198,298,398 | 62,826,881,438 |
| 3 | MSFT | Microsoft Corp | 5.43% | 100,293,740 | 48,573,261,219 |
_Showing results 1-3 of 504 - raise maxResults (max 500) or pass offset=3 to continue._
GetIndexChanges
Returns the companies that have joined or left an index, newest first. Changes are derived by comparing consecutive constituent lists from the funds that track the index, so each one is dated to the window between two reports rather than to an announcement: a daily holdings file dates a change to a day, a quarterly filing only to a quarter. Several funds track the same index and each records a change separately, so records for the same company and direction over overlapping windows are collapsed into the single event a reader should see, keeping the narrowest window. This is observed membership rather than an announcement feed, so a change appears once a tracking fund has actually reported it.
Parameters: index (required: slug or name), maxResults (default 25, max 500).
Ask: "Which companies have joined or left the Nasdaq-100 recently?"
Returns:
## Nasdaq-100 additions and deletions
Derived by comparing consecutive lists from the funds that track this index, so each change is dated to the window between two reports rather than to an announcement.
| Change | Company | Ticker | Observed | Seen between | Weight | Funds |
|---|---|---|---|---|---:|---:|
| Added | Walmart Inc. | WMT | 2026-03-31 | 2025-12-31 to 2026-03-31 | 3.44% | 1 |
| Removed | AstraZeneca PLC | - | 2026-03-31 | 2025-12-31 to 2026-03-31 | 0.3% | 1 |
| Added | Western Digital Corp | WDC | 2025-12-31 | 2025-09-30 to 2025-12-31 | 0.32% | 1 |
GetIndexForecast
Applies an index's own published entry rules to every company we track. Aggregate counts are public; candidate identities, directions, ranks, values, and rule scorecards require a Plus or Pro plan.
The distinction the answer leads with is the one that matters. The S&P indexes use a screen because an S&P Dow Jones Indices committee makes the final decision. The S&P 500 adds a versioned 90-day probability model over that screen: every eligible join candidate and every current member receives an estimate, ordered from most likely to least likely. Other S&P indexes remain raw screens. The Russell indexes and the Nasdaq-100 are projections because their membership is decided by a published ranking.
A company whose figures we could not read is reported in its own entry bucket because a figure we cannot read is not entry evidence. The S&P 500 exit model still gives each current member the common historical baseline. For a projection the ranking is built without unmeasured members, so a company is only shown as joining when its rank would hold even if every unmeasured member outranked it.
The Dow publishes no quantitative entry rule, so it has no forecast and the tool says so rather than inventing one. Snapshots are written once per trading day from settled closes and never revised.
Parameters: index (required: slug or name; the Dow is not forecastable), maxResults (default 25, max 1000, per bucket). Use at least 600 to retrieve every current-member S&P 500 exit estimate in one response.
Ask: "Which companies are most likely to join and leave the S&P 500 in the next 90 days?"
Returns on Free (trimmed):
## S&P 500 rebalance outlook
As of 2026-08-20, 7555 companies were scored.
Potential additions: 27
...
Candidate identities and rule scorecards require a paid Equibles plan. Upgrade at https://equibles.com/Pricing.
Plus and Pro callers receive the candidate tables and rule evidence after the same public summary.