This guide explains how end users, validators, and infrastructure operators can connect MetaMask to Lumera EVM networks.

<aside> ⚠️

The MetaMask RPC URL is NOT the same as the Keplr RPC URL. Keplr is a Cosmos wallet and talks to the Cosmos endpoints (LCD/REST + CometBFT RPC). MetaMask is an EVM wallet and talks only to the Ethereum JSON-RPC endpoint, which is a separate service on a different port and a different URL. Pasting a Keplr/Cosmos URL into MetaMask is the most common reason a connection fails ("could not fetch chain ID").

</aside>

MetaMask connects to EVM networks through Ethereum JSON-RPC. Do not use Cosmos LCD/REST endpoints or CometBFT RPC endpoints as MetaMask RPC URLs. The two wallets use entirely different endpoints:

Only the EVM JSON-RPC row belongs in a MetaMask network configuration. The Cosmos LCD/REST and CometBFT RPC URLs will never answer eth_chainId, so MetaMask cannot use them.

Official references:

• MetaMask custom network guide
• MetaMask eth_chainId reference
• MetaMask wallet_addEthereumChain reference

EVM RPC URLs by Network

The RPC URL you give MetaMask is always the EVM JSON-RPC endpoint (evm-rpc.*) for the target network. The chain ID (76857769) and currency symbol (LUME) are identical on every Lumera network.

The rest of this guide uses the public devnet values as the worked example.

Lumera Devnet Values

Use these values for the public Lumera devnet endpoint operated for the Portal.

The current public RPC can be checked with:

curl -H 'content-type: application/json' \
  --data '{"jsonrpc":"2.0","id":1,"method":"eth_chainId","params":[]}' \
  <https://evm-rpc.pastel.network>

Expected result:

{"jsonrpc":"2.0","id":1,"result":"0x494c1a9"}