Sei Blockchain API

API Overview

Sei is the first parallelized Cosmos chain optimized for DeFi, offering the fastest transaction finality in the ecosystem.

RPC API Endpoints

• RPC: https://sei-rpc.polkachu.com
• REST: https://sei-api.polkachu.com
• WebSocket: wss://sei-ws.polkachu.com
• Block Time: ~400ms finality

JavaScript Example

const { getCosmWasmClient } = require('@sei-js/core');

const rpcEndpoint = "https://sei-rpc.polkachu.com";
const client = await getCosmWasmClient(rpcEndpoint);

// Query contract state
const query = await client.queryContractSmart(
  "sei1...", 
  { get_config: {} }
);
console.log(query);
        

Best For

• DeFi applications (DEX, lending)
• Trading platforms
• Cosmos ecosystem development
• High-frequency trading dApps