# Chain

Retrieve the full option chain — every call and put contract — for any supported underlying symbol, with extensive filtering options.

## Making Requests

Use the `chain()` method on the `options` resource to fetch an option chain. The response includes Greeks (delta, gamma, theta, vega, IV), intrinsic/extrinsic value, and underlying price alongside the quote fields.

| Output Format          | Result Payload                            | Description                                     |
|------------------------|-------------------------------------------|-------------------------------------------------|
| **internal** (default) | `OptionsChain[]` or `OptionsChainHuman[]` | Array of decoded option-contract records.       |
| **json**               | Raw JSON object                           | The compressed, array-keyed response object.    |
| **csv**                | `Blob`                                    | CSV payload. Use `.save(filename)` to write it. |

<a name="chain"></a>
## chain

```typescript
// Positional form
chain<P>(
  symbol: string,
  params?: P,
): MarketDataResult<OptionsChain[] | OptionsChainHuman[]>

// Object form
chain<P>(
  params: P & { symbol: string },
): MarketDataResult<OptionsChain[] | OptionsChainHuman[]>
```

Fetches the option chain for a single underlying symbol.

#### Parameters

- `symbol` (string)

  The underlying stock symbol (e.g. `"AAPL"`).

- `date` (string | Date, optional)

  Fetch the chain as-of a specific historical date (end-of-day snapshot).

- `expiration` (string | Date, optional)

  Filter by specific expiration date.

- `days_to_expiration` (number, optional)

  Filter by number of days to expiration.

- `from` / `to` (string | Date, optional)

  Range filter for expiration dates.

- `month` (number, optional, 1–12), `year` (number, optional)

  Filter by expiration month and/or year.

- `weekly` / `monthly` / `quarterly` (boolean, optional)

  Filter by expiration cycle type.

- `strike` (number | string, optional)

  Filter by specific strike price.

- `delta` (number, optional)

  Filter by target delta value.

- `strike_limit` (number, optional)

  Limit the response to the N strikes nearest the underlying price.

- `range` (string, optional)

  Filter by in-the-money / out-of-the-money range (e.g. `"itm"`, `"otm"`).

- `min_bid` / `max_bid` / `min_ask` / `max_ask` (number, optional)

  Filter by quote price thresholds.

- `max_bid_ask_spread` (number, optional), `max_bid_ask_spread_pct` (number, optional)

  Filter by spread thresholds.

- `min_open_interest` (number, optional), `min_volume` (number, optional)

  Filter by liquidity thresholds.

- `nonstandard` (boolean, optional)

  Include or exclude non-standard contracts.

- `side` (`"call"` | `"put"` | `"both"`, optional)

  Filter by option side.

- `am` / `pm` (boolean, optional)

  Filter by AM-settled or PM-settled contracts.

- [`outputFormat`](/sdk/js/settings#output-format) (optional): The format of the returned data. Alias: `format`.
- [`dateFormat`](/sdk/js/settings#date-format) (optional): Date format. Alias: `dateformat`.
- [`columns`](/sdk/js/settings#columns) (optional): Columns to include.
- [`addHeaders`](/sdk/js/settings#headers) (optional): Whether to include headers in CSV output. Alias: `headers`.
- [`useHumanReadable`](/sdk/js/settings#human-readable) (optional): Use human-readable field names. Alias: `human`.
- [`mode`](/sdk/js/settings#data-mode) (optional): The data mode to use.

#### Returns

- [`MarketDataResult<OptionsChain[] | OptionsChainHuman[] | Blob>`](/sdk/js/client#MarketDataResult)

### Full Chain

```typescript
const client = new MarketDataClient();

const result = await client.options.chain("AAPL");

result.match(
  (contracts) => console.log(`Got ${contracts.length} contracts`),
  (error) => console.error(error.message),
);
```

### Filtered

```typescript
const client = new MarketDataClient();

// Calls only, narrow strike window, high open interest
const result = await client.options.chain("AAPL", {
  side: "call",
  strike_limit: 10,
  min_open_interest: 100,
});

result.match(
  (contracts) => {
    for (const c of contracts) {
      console.log(
        `${c.optionSymbol} strike=${c.strike} mid=${c.mid} delta=${c.delta} oi=${c.openInterest}`
      );
    }
  },
  (error) => console.error(error.message),
);
```

### Historical

```typescript
const client = new MarketDataClient();

const result = await client.options.chain("AAPL", {
  date: "2024-01-15",
  expiration: "2024-02-16",
  side: "call",
});

result.match(
  (contracts) => console.log(contracts),
  (error) => console.error(error.message),
);
```

### Human Readable

```typescript
const client = new MarketDataClient();

const result = await client.options.chain("AAPL", {
  side: "put",
  human: true,
});

result.match(
  (contracts) => {
    for (const c of contracts) {
      console.log(
        `${c.Symbol} Strike=${c.Strike} Mid=${c.Mid} Delta=${c.Delta}`
      );
    }
  },
  (error) => console.error(error.message),
);
```

<a name="OptionsChain"></a>
## OptionsChain

```typescript
interface OptionsChain {
  s?: string;
  optionSymbol: string;
  underlying: string;
  expiration: number;
  side: string;
  strike: number;
  firstTraded: number;
  dte: number;
  updated: number;
  bid: number | null;
  bidSize: number | null;
  mid: number | null;
  ask: number | null;
  askSize: number | null;
  last: number | null;
  openInterest: number | null;
  volume: number | null;
  inTheMoney: boolean;
  intrinsicValue: number;
  extrinsicValue: number;
  underlyingPrice: number;
  iv: number | null;
  delta: number | null;
  gamma: number | null;
  theta: number | null;
  vega: number | null;
}
```

#### Properties

- `optionSymbol` (string): OCC-format option symbol (e.g. `"AAPL271217C00250000"`).
- `underlying` (string): The underlying stock symbol.
- `expiration` (number): Unix timestamp of the expiration date.
- `side` (string): `"call"` or `"put"`.
- `strike` (number): The strike price.
- `firstTraded` (number): Unix timestamp when the contract first traded.
- `dte` (number): Days to expiration.
- `updated` (number): Unix timestamp when the quote was last updated.
- `bid`, `ask`, `mid`, `last` (number | null): Quote prices.
- `bidSize`, `askSize` (number | null): Quote sizes.
- `openInterest`, `volume` (number | null): Liquidity metrics.
- `inTheMoney` (boolean): Whether the contract is currently in the money.
- `intrinsicValue`, `extrinsicValue` (number): Value decomposition.
- `underlyingPrice` (number): Price of the underlying at quote time.
- `iv`, `delta`, `gamma`, `theta`, `vega` (number | null): Implied volatility and Greeks.

<a name="OptionsChainHuman"></a>
## OptionsChainHuman

When `human: true` is set, field names are returned in `Title_Case`: `Symbol`, `Underlying`, `Expiration_Date`, `Option_Side`, `Strike`, `Days_To_Expiration`, `Bid`, `Ask`, `Mid`, `Open_Interest`, `Volume`, `In_The_Money`, `IV`, `Delta`, `Gamma`, `Theta`, `Vega`, etc.