Free Sei RPC Endpoint

Sei is a Cosmos-based chain with a native EVM runtime — and among the fastest finality of any EVM chain in production: blocks finalize at ~400 ms with no reorgs and no confirmation-count waiting. Parallel transaction execution keeps throughput high under load. Few independent RPC providers serve Sei EVM yet; NodeFlare runs a dedicated node so you can start building in under a minute.

Sei RPC URLs#

Public endpoint — no API key:

https://rpc.nodeflare.app/sei/public

Keyed endpoint (free account — higher limits, heavy methods):

https://rpc.nodeflare.app/sei/v1/{YOUR_KEY}

Get your free key → — no credit card.

Quick start#

curl https://rpc.nodeflare.app/sei/public \
  -X POST \
  -H "Content-Type: application/json" \
  -d '{"jsonrpc":"2.0","method":"eth_blockNumber","params":[],"id":1}'

import { ethers } from 'ethers';

const provider = new ethers.JsonRpcProvider(
  'https://rpc.nodeflare.app/sei/public'
);
console.log('Sei block:', await provider.getBlockNumber());

Sei at a glance#

Sei's ~0.4 s blocks mean a day's worth of history is over 200,000 blocks — the fastest-accumulating block ranges of any chain we serve. Block-range arithmetic from Ethereum tooling is off by 30×: a “7 days ≈ 50,000 blocks” assumption from mainnet is wrong here. Our per-method reference covers chain-specific notes for every JSON-RPC method.

One important quirk: eth_syncing is not implemented on Sei nodes — the method returns an error instead of false. Use block-height comparison to check sync status in health checks.

Free tier#

• 2,000,000 compute units/month — no credit card
• eth_getLogs (75 CU), trace_*/debug_* (100 CU) included on free
• All 23 supported chains under one key — Sei, Ethereum, Base, Arbitrum and more
• Geo-routed with automatic failover

Add Sei to MetaMask#

FAQ#

What is the Sei RPC URL? https://rpc.nodeflare.app/sei/public — no API key required, rate-limited per IP. A free key unlocks higher limits and heavy methods.

Is the Sei EVM RPC free? Yes. The public endpoint is free without sign-up; a free account adds 2M CU/month and a dedicated keyed path — no credit card.

Does eth_getLogs work on Sei? Yes — with a free API key. At 200,000+ blocks/day, keep windows tight with address + topic filters: each call costs 75 CU.

Does Sei support WebSocket? Not on the current NodeFlare endpoint. HTTP JSON-RPC is available across all 23 chains; WebSocket is live on Ethereum, Base, BNB Chain, Arbitrum, Optimism, HyperEVM, and Avalanche.

What makes Sei EVM different from other chains? Sei isn't an L2 rollup — it's a sovereign Cosmos chain running a native EVM. That means single-block finality (~400 ms, no reorgs ever) and parallel transaction execution rather than sequential processing. Most EVM providers don't serve it independently; aggregators that resell Alchemy or Infura don't reach Sei at all.

Building on Sei? Get your free NodeFlare key → — covers Sei plus all 23 supported chains.