# Donchian Channel Breakout Screener (Multi-Asset) API
> Which markets are breaking out of their recent trading range, computed live from Yahoo Finance (no key, nothing stored). The Donchian channel — the highest high and lowest low of the last N days — is the breakout system the legendary Turtle traders rode: a close above the 20-day high is a classic long entry, below the 20-day low a short, and the 55-day channel is the slower, higher-conviction version. For a cross-asset, cross-sector universe — equity indices and sectors, gold, oil, commodities, bonds and crypto — this computes each asset's 20-day and 55-day Donchian channels (upper, lower and midline), where price sits inside the 20-day channel, and flags fresh breakouts above the high or below the low. The screener endpoint returns the upside and downside breakouts across the board plus the channel-position ranking. The asset endpoint returns one market's Donchian card. The universe endpoint lists what is covered. The cross-asset Donchian / channel-breakout (Turtle) screener cut — distinct from the crypto-only Donchian screener, the 52-week-range screener (a much longer window), the Bollinger-Bands screener and the bring-your-own-candle indicator APIs. It catches the range breakouts across every asset class at once.

## 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/donchian-api/..."
```

## Pricing
- **Free** (Free) — 760 calls/Mo, 2 req/s
- **Starter** ($11/Mo) — 17,000 calls/Mo, 6 req/s
- **Pro** ($33/Mo) — 89,500 calls/Mo, 16 req/s
- **Business** ($76/Mo) — 486,000 calls/Mo, 40 req/s

## Endpoints

### Screener

#### `GET /v1/screener` — Cross-asset board with 20/55-day breakouts and channel-position ranking

**Parameters:**
- `class` (query, optional, string) — Filter by class: equities, sector, commodities, bonds, crypto Example: `commodities`

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/donchian-api/v1/screener?class=commodities"
```

### Asset

#### `GET /v1/asset` — One market Donchian channel card

**Parameters:**
- `asset` (query, required, string) — Asset key (see /v1/universe) Example: `sp500`

**Example:**
```bash
curl -H "x-oanor-key: $KEY" \
  "https://api.oanor.com/donchian-api/v1/asset?asset=sp500"
```

### Universe

#### `GET /v1/universe` — Supported instruments

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

### Meta

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

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


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