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Run safely

Start with Ethereum reads

Read an ETH balance and block number using Cloud RPC and Test mode.

Ethereum currently has two read nodes: ETH balance and Ethereum block number. They inspect public data without signing or spending ETH. Token balances, transfers, swaps, and event watchers are not available yet.

Set up your first read#

  1. Sign in, choose the Browser runtime, and select Cloud RPC in RPC settings. Blokboard manages the connection; you do not enter a provider API key.
  2. Import the Ethereum wallet snapshot. It starts with Test mode on. Ethereum uses Sepolia for test data and mainnet when Test mode is off; the switch selects the route automatically.
  3. Set the workflow Global walletAddress to a public Ethereum address: 0x followed by 40 hexadecimal characters. You do not need its private key, a saved wallet, or test funds to read it.
  4. Run once and inspect the block number, ETH balance, and final Variable output. A zero balance is valid. The same address can hold different balances on test and live networks.

Understand the values#

ETH balance returns address, eth, wei, network, and chainId. ETH and wei are decimal strings, preserving the full amount. One ETH is 1,000,000,000,000,000,000 wei. Avoid converting large wei amounts to JavaScript Number.

Ethereum block number returns blockNumber as a decimal string and the network. It does not return transactions or the block’s timestamp. Separate reads are not an atomic snapshot at one block.

Both nodes check the RPC chain ID before reading. That verifies the selected route; it does not submit a transaction. The example costs 30 Cloud RPC credits per complete run. Read credits and throttling before repeating it in a loop.

Use another RPC route#

Custom RPC lets you provide your own Ethereum endpoint in RPC settings for the workflow’s selected mode. Desktop and Extension can use Public RPC. Keep private endpoint credentials in runtime settings, outside downloadable workflows.

If the result is unexpected#

  • Zero ETH: confirm Test mode and the address. A mainnet balance does not also exist on the test network.
  • Wrong network: the custom endpoint does not match Test mode. Correct the endpoint or the mode before rerunning.
  • Invalid address: use a public 0x address, not an ENS name or private key.
  • Busy or insufficient credits: follow the RPC guidance.