# US Equity Market Breadth API
> How broad the US stock market's move really is under the surface, computed live from Yahoo Finance across a large-cap universe (no key, nothing stored). The S&P 500 can be dragged up by a handful of megacaps while most stocks fall; breadth tells you how many stocks are actually participating. The breadth endpoint scans a ~50-name large-cap universe spanning every sector and returns the share trading above their 20-, 50- and 200-day moving averages (the classic participation gauges), the advancers versus decliners on the day, the advance/decline ratio, the average and median daily change and a regime label (broad strength, mixed or broad weakness). The components endpoint returns the per-stock table behind it — each name's price, daily change and whether it is above each moving average — so you can see exactly which stocks are carrying or dragging the market. The constituents endpoint lists the universe. The equity market-internals / breadth cut — distinct from the crypto-breadth API (which scans coins), the single-quote, index-constituent and movers APIs. It answers whether a rally is broad or narrow, not how one stock is doing.

## Authentication
All requests require your oanor API key in the `x-oanor-key` header. Get one at https://www.oanor.com/developer/keys.

```bash
curl -H "x-oanor-key: oanor_live_…" "https://api.oanor.com/equitybreadth-api/..."
```

## Pricing
- **Free** (Free) — 850 calls/Mo, 2 req/s
- **Starter** ($10/Mo) — 19,500 calls/Mo, 6 req/s
- **Pro** ($31/Mo) — 98,000 calls/Mo, 16 req/s
- **Business** ($73/Mo) — 520,000 calls/Mo, 40 req/s

## Endpoints

### Breadth

#### `GET /v1/breadth` — Market-wide breadth: % above MAs, advance/decline, regime

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/equitybreadth-api/v1/breadth"
```

### Components

#### `GET /v1/components` — Per-stock breadth table (price, daily change, above each MA)

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/equitybreadth-api/v1/components"
```

### Constituents

#### `GET /v1/constituents` — The large-cap universe used

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/equitybreadth-api/v1/constituents"
```

### Meta

#### `GET /v1/meta` — Service metadata

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/equitybreadth-api/v1/meta"
```


---
Marketplace page: https://www.oanor.com/api/equitybreadth-api
OpenAPI spec: https://www.oanor.com/api/equitybreadth-api/openapi.json