> For the complete documentation index, see [llms.txt](https://docs.harmony.one/home/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.harmony.one/home/general/ecosystem/wallets/browser-extensions-wallets/metamask-wallet/adding-harmony.md).

# Adding Harmony

### Adding Harmony to MetaMask

Open MetaMask and click the list of networks at the top, then select "Add Network".

![](/files/TkczpFrVZAkGCxDJc8rJ)

### Fill the Endpoint Information

You will be prompted for additional information. Use the table below to complete the step. Below you will see multiple options for RPC URL and Chain ID corresponding to mainnet vs testnet, and the various shards within each.

{% hint style="info" %}
**Use the RPC URL and Chain ID of Shard 0 if you want to send/receive transactions from exchanges or do any staking transaction type.**
{% endhint %}

| Field                                                    | Mainnet                                                                        | Testnet                                                                       | Devnet                                                            |
| -------------------------------------------------------- | ------------------------------------------------------------------------------ | ----------------------------------------------------------------------------- | ----------------------------------------------------------------- |
| **Network Name**                                         | Harmony Mainnet                                                                | Harmony Testnet                                                               | Harmony Devnet                                                    |
| **New RPC URL**                                          | <p><https://api.harmony.one></p><p><https://s1.api.harmony.one></p><p></p>     | <p><https://api.s0.b.hmny.io></p><p><https://api.s1.b.hmny.io></p>            | <p><https://api.s0.ps.hmny.io><br><https://api.s1.ps.hmny.io></p> |
| <p><strong>Chain ID</strong></p><p>(use number only)</p> | <p>Shard 0: <code>1666600000</code></p><p>Shard 1: <code>1666600001</code></p> | <p>Shard 0: <code>1666700000</code><br>Shard 1: <code>1666700001</code></p>   | <p>Shard 0: 1666900000<br>Shard 1: 1666900001</p>                 |
|                                                          |                                                                                |                                                                               |                                                                   |
| **Currency symbol (optional)**                           | ONE                                                                            | ONE                                                                           | ONE                                                               |
| **Block Explorer URL (optional)**                        | <https://explorer.harmony.one/>                                                | [https://explorer.testnet.harmony.one/](https://explorer.testnet.harmony.one) | <https://explorer.ps.hmny.io>                                     |

The example below shows the configuration that needs to be done to connect to Harmony Mainnet on Shard 0:

![](/files/-MiXjTqOCA7JFAbQbcXz)

Click the Save button and your configuration should be done!

{% hint style="success" %}
if you have any issue fetching data like chain-id, try to type the `new RPC URL` instead copy pasting it.
{% endhint %}


---

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