Unichain Sepolia RPC & API Endpoints

Unichain’s Sepolia Testnet

Chain ID1301

CurrencyETH

Connect to Unichain Sepolia RPC endpoints for wallet flows, contract apps, and live backends, with archive and trace support where supported.

Unichain’s Sepolia Testnet

Create RPC Endpoint

Unichain Sepolia RPC Endpoint

The below example uses the public API endpoint*. This endpoint is only suitable for testing. To avoid rate limiting and service interruption, sign up now to get your own API key.

Example CURL

curl -H 'content-type:application/json' -d '{"id": 1, "jsonrpc": "2.0", "method": "eth_blockNumber"}' 'https://unichain-sepolia.api.onfinality.io/public'

curl -H 'content-type:application/json' -d '{"id": 1, "jsonrpc": "2.0", "method": "eth_blockNumber"}' 'https://unichain-sepolia.api.onfinality.io/public'

HTTPs

https://unichain-sepolia.api.onfinality.io/public

https://unichain-sepolia.api.onfinality.io/public

Websocket

wss://unichain-sepolia.api.onfinality.io/public-ws

wss://unichain-sepolia.api.onfinality.io/public-ws

* The public endpoint is rate limited

RPC API Service

RPC API Features

ArchiveTrace

PRICING

Calculate Your Costs

Only pay for what you need.

Monthly Response Units

Million Standard Requests

0100M200M300M400M

Total Cost

$49/ month

Recommended Plan: GROWTH

Continue with this plan

Unichain Sepolia RPC Endpoints

Unichain Sepolia is the official testnet for Unichain, a DeFi-focused Ethereum Layer 2 built on the OP Stack. It provides a sandbox environment for developers to test dApps, smart contracts, and DeFi protocols before deploying to mainnet. OnFinality offers managed RPC API endpoints for Unichain Sepolia, giving you reliable access to the testnet without running your own node.

What is Unichain Sepolia?

Unichain Sepolia is an EVM-compatible testnet that mirrors the Unichain mainnet environment. It uses ETH as gas and supports all standard Ethereum JSON-RPC methods, plus rollup-specific methods. Developers use it to test Uniswap-focused DeFi applications, cross-chain liquidity features, and other smart contract interactions in a low-risk setting.

Why Use OnFinality for Unichain Sepolia RPC?

Running a Unichain Sepolia node yourself can be time-consuming and resource-intensive. OnFinality provides:

Managed API endpoints: HTTP and WebSocket access to Unichain Sepolia.
Archive and trace support: Access historical state and debug transactions where available.
Observability: Request analytics and usage metrics to monitor your application.
Scalability: A clear path from shared endpoints to higher-capacity plans.

How to Connect to Unichain Sepolia

Create or sign in to your OnFinality account.
Select Unichain Sepolia from the supported networks list.
Create an API endpoint (shared or dedicated if supported).
Use the provided URL in your Web3 library (e.g., ethers.js, web3.js).
Test with eth_blockNumber and monitor usage.

Use Cases

dApp development: Test wallet integrations, transaction flows, and UI interactions.
Smart contract testing: Deploy and debug contracts in a realistic environment.
DeFi prototyping: Experiment with liquidity pools, swaps, and yield strategies.
Analytics and tooling: Build indexers, dashboards, and monitoring tools.

Key Facts

Network: Testnet (Sepolia)
Chain ID: 1301
Protocol: EVM JSON-RPC
Transport: HTTP, WebSocket
Advanced features: Archive, trace (plan-dependent)
Common users: Developers, QA teams, DeFi projects

Get Started

OnFinality makes it easy to access Unichain Sepolia RPC endpoints. Sign up today and start building on the Unichain testnet with reliable infrastructure.

Unichain Sepolia RPC and developer resources

A useful Unichain Sepolia RPC page should make the connection path, supported capabilities, and production planning trade-offs clear before a developer opens the dashboard.

Best fit: mainnet production workflows for wallet flows, contract apps, and live backends.

What builders usually check first:

Read current chain state for apps, dashboards, wallets, and backend services.
Submit transactions and monitor confirmations from Ethereum-compatible tools.
Query logs, receipts, and historical state when indexers or analytics pipelines need more than the latest block.
Debug contract behaviour with trace data where the network supports it.

Supported capability notes:

Authenticated Unichain Sepolia RPC/API access for wallet flows, contract apps, and live backends.
Flexible HTTP and WebSocket access for app, backend, and integration workflows.
Archive-capable workflows when the product needs older chain state.
Trace-ready workflows for teams that need to inspect execution paths.

Decision notes:

Environment: mainnet. Protocol family: EVM JSON-RPC.
Flexible HTTP and WebSocket access is listed for supported app and backend workflows.
Archive support is available for historical state or older chain-data queries.
Trace support is available for transaction debugging and execution analysis.

A quick connection check usually starts with eth_blockNumber, then moves into the exact methods your wallet, dashboard, bot, indexer, or backend service needs.

Planning the next step:

Shared RPC is a practical starting point for integration, prototypes, dashboards, and many app backends.
If your product becomes traffic-heavy or operationally sensitive, review the available upgrade path before relying on a single access pattern.

Next steps: