> ## Documentation Index
> Fetch the complete documentation index at: https://docs.cow.bleu.builders/llms.txt
> Use this file to discover all available pages before exploring further.

# Orders

> Creating and managing CoW Protocol orders using the TypeScript SDK

# Orders

The `Order` interface represents a Gnosis Protocol v2 order with specific required fields for signing and settlement.

## Order Interface

```typescript theme={null}
interface Order {
  sellToken: string;
  buyToken: string;
  receiver: string;
  sellAmount: BigNumberish;
  buyAmount: BigNumberish;
  validTo: number | Date;
  appData: string;
  feeAmount: BigNumberish;
  kind: OrderKind;
  partiallyFillable: boolean;
  sellTokenBalance?: OrderBalance;
  buyTokenBalance?: OrderBalance;
}
```

## Order Types

### Sell Orders

Specify an exact amount to sell with a minimum amount to receive:

```typescript theme={null}
const sellOrder: Order = {
  sellToken: WETH,
  buyToken: DAI,
  sellAmount: ethers.utils.parseEther("1.0"),   // Exact
  buyAmount: ethers.utils.parseEther("2000"),    // Minimum
  kind: OrderKind.SELL,
  // ...
};
```

### Buy Orders

Specify an exact amount to receive with a maximum to spend:

```typescript theme={null}
const buyOrder: Order = {
  sellToken: WETH,
  buyToken: DAI,
  sellAmount: ethers.utils.parseEther("1.1"),    // Maximum
  buyAmount: ethers.utils.parseEther("2000"),     // Exact
  kind: OrderKind.BUY,
  // ...
};
```

## Balance Management

Three balance modes are supported:

| Mode     | Enum                    | Description                      |
| -------- | ----------------------- | -------------------------------- |
| Standard | `OrderBalance.ERC20`    | Standard ERC20 token transfers   |
| External | `OrderBalance.EXTERNAL` | Balancer Vault external balances |
| Internal | `OrderBalance.INTERNAL` | Balancer Vault internal balances |

## Utility Functions

### normalizeOrder

Prepares orders for EIP-712 signing by converting Date objects to timestamps and normalizing optional fields.

```typescript theme={null}
import { normalizeOrder } from "@cowprotocol/contracts";

const normalized = normalizeOrder(order);
```

### hashOrder

Generates the EIP-712 hash needed for cryptographic signing.

```typescript theme={null}
import { hashOrder, domain } from "@cowprotocol/contracts";

const settlementDomain = domain(1, "0x9008D19f58AAbD9eD0D60971565AA8510560ab41");
const hash = hashOrder(settlementDomain, order);
```

### computeOrderUid

Creates a 56-byte unique identifier combining order digest, owner address, and expiration.

```typescript theme={null}
import { computeOrderUid } from "@cowprotocol/contracts";

const uid = computeOrderUid(settlementDomain, order, ownerAddress);
```

### extractOrderUidParams

Decodes order UID components back into individual parameters.

```typescript theme={null}
import { extractOrderUidParams } from "@cowprotocol/contracts";

const { orderDigest, owner, validTo } = extractOrderUidParams(uid);
```

## Constants

```typescript theme={null}
// Special address for purchasing native ETH (use only in buyToken field)
const BUY_ETH_ADDRESS = "0xEeeeeEeeeEeEeeEeEeEeeEEEeeeeEeeeeeeeEEeE";

// Order UID length in bytes
const ORDER_UID_LENGTH = 56;
```

<Warning>
  `BUY_ETH_ADDRESS` should only be used in the `buyToken` field. Using it elsewhere will cause unexpected behavior.
</Warning>