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

# Whitechain Sepolia (testnet)

> Network reference for the Whitechain Sepolia testnet: how to connect, public RPC limits, fees, and withdrawal timing. This reference is provided for testing and evaluation purposes only. Testnet parameters and endpoints are offered on an "AS IS" and "AS AVAILABLE" basis without uptime SLAs or warranties.

## At a glance

| Parameter | Value |
| - | - |
| Network name | Whitechain Sepolia |
| Short name | WCH Sepolia |
| Chain ID | `1874` (hex `0x752`) |
| L1 | Ethereum Sepolia (`11155111`) |
| Gas token | WBT (WhiteBIT Coin, 18 decimals). Testnet tokens carry no economic value |
| L2 block time | 1s |
| Flashblocks | Not enabled |

Flashblocks are not enabled on this network. The rollout is prepared and no date is set, so no interval is published. Once enabled, they are preconfirmations the sequencer streams ahead of each full one-second L2 block, they carry the sequencer's word only, and they do not change when a transaction becomes safe or finalized. Forward-looking features and deployment schedules remain subject to modification or cancellation without prior notice. See [Flashblocks in Transaction finality](/learn/network/transaction-finality#flashblocks) for the mechanism and how the three confirmation stages differ.

## Endpoints

| Type | URL |
| - | - |
| Public RPC | `https://rpc.testnet.whitechain.io` |
| WebSocket | `wss://rpc.testnet.whitechain.io/ws` |
| Explorer | [explorer.testnet.whitechain.io](https://explorer.testnet.whitechain.io) |
| Faucet | [faucet.testnet.whitechain.io](https://faucet.testnet.whitechain.io) |
| Bridge | [bridge.testnet.whitechain.io](https://bridge.testnet.whitechain.io) |

To check current uptime for these endpoints, see the [status page](https://status.whitechain.io/). Whitechain does not guarantee unbroken service availability, response rates, or uninterrupted operation of public infrastructure.

## Public RPC rate limits

The public RPC is rate limited per client IP address. When you exceed the limit, the endpoint returns `429 Too Many Requests` with a `Retry-After` header.

| Property | Value |
| - | - |
| Sustained rate | 50 requests per second per client IP |
| Burst allowance | Up to 500 requests above the sustained rate |
| What the limit counts | Each HTTP request, not each JSON-RPC call inside a batch |
| Status code when you are limited | `429 Too Many Requests` |
| Retry hint | `Retry-After: 1` header on every `429` response |
| WebSocket limits | Published once they are finalized |

The public RPC and WebSocket endpoints need no API key and no IP allowlist. Reads and writes are open to any client, subject to the limits above. No third-party public endpoint serves Whitechain Sepolia yet. For the full list of public endpoints across networks, including planned third-party endpoints, and for guidance on handling `429` responses, see [Public RPC endpoints](/learn/network/reference#public-rpc-endpoints).

## WebSocket and subscriptions

The node exposes a WebSocket endpoint at `wss://rpc.testnet.whitechain.io/ws`. It serves the standard Ethereum JSON-RPC API and supports `eth_subscribe` for real-time updates, including `newHeads`, `logs`, and `newPendingTransactions`. Reuse one connection for multiple subscriptions rather than opening a connection per query. See [Public RPC rate limits](#public-rpc-rate-limits) for the limits that apply.

## Fees

Whitechain uses EIP-1559 with a 1-second block time, so fees stay low and predictable. Gas mechanics aim for fee stability, but execution costs remain subject to variable L1/L2 network demand and gas price fluctuations.

<Accordion title="All fee parameters">
  | Parameter | Value |
  | - | - |
  | `baseFeeScalar` | 100000 |
  | `blobBaseFeeScalar` | 1000000 |
  | `operatorFeeScalar` | 0 |
  | `operatorFeeConstant` | 0 |
  | `gasLimit` | 40000000 |
  | `minimumGasLimit` | 21000000 |
  | `maximumGasLimit` | 500000000 |
  | `eip1559Elasticity` | 6 |
  | `eip1559Denominator` | 100. `eip1559DenominatorCanyon` is 250, but never applies here because Holocene is active from genesis |
  | `minBaseFee` | 5000000000 wei, that is 5 gwei. The L2 base fee never drops below it |
</Accordion>

## Withdrawals

L2 withdrawals finalize after the dispute window ends. On testnet the dispute delays total 20 minutes, but a full withdrawal takes about an hour, and up to three hours in the worst case. A withdrawal can only be proven against a dispute game that covers its L2 block, and the proposer publishes a new game every 30 minutes. Whitechain Mainnet is not live, so its figure is not published; on OP Mainnet a withdrawal takes a minimum of 7 days. The spread between one hour and three comes from L1 block finality and from how long dispute resolution takes. See [OP Stack canonical bridge](/build/bridge/bridge-assets#timing-parameters) for the full breakdown.

<Accordion title="Dispute game parameters">
  | Parameter | Value (seconds) |
  | - | - |
  | `proofMaturityDelaySeconds` | 900 |
  | `disputeGameFinalityDelaySeconds` | 300 |
  | `faultGameWithdrawalDelay` | 600 |
  | `faultGameClockExtension` | 300 |
  | `faultGameMaxClockDuration` | 900 |
  | `preimageOracleChallengePeriod` | 300 |
</Accordion>

## Related

* [Connect to Whitechain Sepolia](/learn/get-started/connect-wallet)
* [Deploy a contract](/learn/get-started/deploy-a-contract)
* [Next dapp template](/build/dapps/dapp-with-nextjs)
* [Transaction finality](/learn/network/transaction-finality)
* [Service status](https://status.whitechain.io/)


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