> For the complete documentation index, see [llms.txt](https://docs.stacks.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.stacks.co/reference/stacks.js/stacks-network/constants/addressversion.md).

# AddressVersion

Enum representing the address version byte used in encoded Stacks addresses. The address version determines the address type and network.

Every Stacks address starts with `S` followed by a single character indicating the address version. The second character is the c32-encoded `AddressVersion` byte.

***

### Usage

```ts
import { AddressVersion } from '@stacks/network';

// Check if an address version is for mainnet single-sig
if (addressVersion === AddressVersion.MainnetSingleSig) {
  console.log('This is a mainnet single-sig address (SP...)');
}
```

[**Reference Link**](https://github.com/stx-labs/stacks.js/tree/main/packages/network/src/constants.ts#L45)

***

### Definition

```ts
enum AddressVersion {
  MainnetSingleSig = 22,
  MainnetMultiSig = 20,
  TestnetSingleSig = 26,
  TestnetMultiSig = 21,
}
```

***

### Values

| Value              | Number | Address Prefix | Description                                   |
| ------------------ | ------ | -------------- | --------------------------------------------- |
| `MainnetSingleSig` | `22`   | `SP`           | Single-sig address for mainnet                |
| `MainnetMultiSig`  | `20`   | `SM`           | Multi-sig address for mainnet                 |
| `TestnetSingleSig` | `26`   | `ST`           | Single-sig address for testnet/devnet/mocknet |
| `TestnetMultiSig`  | `21`   | `SN`           | Multi-sig address for testnet/devnet/mocknet  |


---

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