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

# Supported Chains

## Plasma

A Layer 1 blockchain backed by Bitfinex, designed as a dedicated settlement layer for USD₮. [Plasma](https://www.plasma.to/) uses PlasmaBFT consensus for sub-second block finality and a protocol-level Paymaster that sponsors direct USDT0 transfers with zero gas fees.

### Mainnet

| Parameter                       | Value                                  |
| ------------------------------- | -------------------------------------- |
| **Network name**                | Plasma Mainnet Beta                    |
| **Chain ID**                    | `9745`                                 |
| **Network identifier (CAIP-2)** | `eip155:9745`                          |
| **Native token**                | XPL                                    |
| **RPC**                         | `https://rpc.plasma.to`                |
| **WebSocket**                   | —                                      |
| **Block explorer**              | [plasmascan.to](https://plasmascan.to) |
| **Block time**                  | Sub-second                             |
| **EVM compatible**              | Yes                                    |

### Testnet

| Parameter          | Value                                                  |
| ------------------ | ------------------------------------------------------ |
| **Network name**   | Plasma Testnet                                         |
| **Chain ID**       | `9746`                                                 |
| **RPC**            | `https://testnet-rpc.plasma.to`                        |
| **Block explorer** | [testnet.plasmascan.to](https://testnet.plasmascan.to) |
| **Faucet**         | [gas.zip/faucet/plasma](https://gas.zip/faucet/plasma) |

### USDT0 on Plasma

| Contract          | Address                                                                                                                  |   |
| ----------------- | ------------------------------------------------------------------------------------------------------------------------ | - |
| **USDT0 token**   | [`0xB8CE59FC3717ada4C02eaDF9682A9e934F625ebb`](https://plasmascan.to/address/0xB8CE59FC3717ada4C02eaDF9682A9e934F625ebb) |   |
| **OFT adapter**   | [`0x02ca37966753bDdDf11216B73B16C1dE756A7CF9`](https://plasmascan.to/address/0x02ca37966753bDdDf11216B73B16C1dE756A7CF9) |   |
| **Decimals**      | 6                                                                                                                        |   |
| **LayerZero EID** | 30383                                                                                                                    |   |

### Links

* [Plasma docs](https://www.plasma.to/docs/plasma-chain/introduction/start-here)
* [Zero-fee USDT transfers](https://www.plasma.to/docs/plasma-chain/stablecoin-native-contracts/zero-fee-usdt-transfers)
* [Bridge via Stargate](https://stargate.finance/bridge?srcChain=ethereum\&srcToken=0xdAC17F958D2ee523a2206206994597C13D831ec7\&dstChain=plasma\&dstToken=0xB8CE59FC3717ada4C02eaDF9682A9e934F625ebb)

***

## Stable

A "stablechain" — a Layer 1 where USDT0 is the native gas and settlement token. [Stable](https://www.stable.xyz/) features sub-second block finality, full EVM compatibility, and native USDT0 transfers at the protocol level. Gas fees are paid in USDT0 directly.

### Mainnet

| Parameter                       | Value                                    |
| ------------------------------- | ---------------------------------------- |
| **Network name**                | Stable Mainnet                           |
| **Chain ID**                    | `988`                                    |
| **Network identifier (CAIP-2)** | `eip155:988`                             |
| **Gas token**                   | USDT0                                    |
| **Governance token**            | STABLE                                   |
| **RPC**                         | `https://rpc.stable.xyz`                 |
| **WebSocket**                   | `wss://rpc.stable.xyz`                   |
| **Block explorer**              | [stablescan.xyz](https://stablescan.xyz) |
| **Block time**                  | ≈0.7 seconds                             |
| **EVM compatible**              | Yes                                      |

### Testnet

| Parameter          | Value                                                    |
| ------------------ | -------------------------------------------------------- |
| **Network name**   | Stable Testnet                                           |
| **Chain ID**       | `2201`                                                   |
| **RPC**            | `https://rpc.testnet.stable.xyz`                         |
| **WebSocket**      | `wss://rpc.testnet.stable.xyz`                           |
| **Block explorer** | [testnet.stablescan.xyz](https://testnet.stablescan.xyz) |
| **Faucet**         | [faucet.stable.xyz](https://faucet.stable.xyz)           |

### USDT0 on Stable

| Contract          | Address                                                                                                                   |
| ----------------- | ------------------------------------------------------------------------------------------------------------------------- |
| **USDT0 token**   | [`0x779Ded0c9e1022225f8E0630b35a9b54bE713736`](https://stablescan.xyz/address/0x779Ded0c9e1022225f8E0630b35a9b54bE713736) |
| **OFT adapter**   | [`0xedaba024be4d87974d5aB11C6Dd586963CcCB027`](https://stablescan.xyz/address/0xedaba024be4d87974d5aB11C6Dd586963CcCB027) |
| **Decimals**      | 6                                                                                                                         |
| **LayerZero EID** | 30396                                                                                                                     |

### Links

* [Stable docs](https://docs.stable.xyz/en/introduction/why-stable)
* [Mainnet information](https://docs.stable.xyz/en/developers/mainnet/mainnet-information)
* [Quick start](https://docs.stable.xyz/en/developers/quick-start)

***

## Funding your wallet

To use x402 on Plasma or Stable, you need USDT0 on the target chain. Bridge USDT from Ethereum or any supported chain using the [USDT0 bridge](https://usdt0.to/transfer).

1. Go to [usdt0.to/transfer](https://usdt0.to/transfer)
2. Select your source chain and USDT
3. Select **Plasma** or **Stable** as the destination
4. Enter the amount and confirm the transaction

USDT is converted to USDT0 automatically during the bridge. No separate swap needed.

***

## Quick reference

For copy-paste into your code:

```typescript theme={null}
import { WalletAccountEvm } from "@tetherto/wdk-wallet-evm";

// Plasma
export const PLASMA_CHAIN_ID = 9745;
export const PLASMA_NETWORK = "eip155:9745";
export const PLASMA_RPC = "https://rpc.plasma.to";
export const PLASMA_USDT0 = "0xB8CE59FC3717ada4C02eaDF9682A9e934F625ebb";

// Stable
export const STABLE_CHAIN_ID = 988;
export const STABLE_NETWORK = "eip155:988";
export const STABLE_RPC = "https://rpc.stable.xyz";
export const STABLE_USDT0 = "0x779Ded0c9e1022225f8E0630b35a9b54bE713736";

// Shared
export const USDT0_DECIMALS = 6;

// Plasma wallet
const plasmaAccount = new WalletAccountEvm(process.env.SEED_PHRASE, {
  provider: PLASMA_RPC,
});

// Stable wallet
const stableAccount = new WalletAccountEvm(process.env.SEED_PHRASE, {
  provider: STABLE_RPC,
});

// Check USDT0 balance on either chain
const plasmaBalance = await plasmaAccount.getTokenBalance(PLASMA_USDT0);
const stableBalance = await stableAccount.getTokenBalance(STABLE_USDT0);

console.log("Plasma USDT0:", Number(plasmaBalance) / 10 ** USDT0_DECIMALS);
console.log("Stable USDT0:", Number(stableBalance) / 10 ** USDT0_DECIMALS);
```

***

## Coming soon

### Solana

Solana support is coming soon. Semantic will support x402 payments settled on Solana using native USDT.

### Spark (Bitcoin)

Spark is a Layer 2 for Bitcoin that enables near-instant, fee-free BTC transactions via Spark invoices. Semantic will support x402 payments settled on Spark, bringing Bitcoin payments to the x402 protocol without on-chain fees or confirmation delays.