Get on the PayPerByte testnet
PayPerByte runs on Arbitrum Sepolia (an Ethereum L2 testnet). Everything below is free — testnet ETH for gas and a public mint for testnet USDC. About 10 minutes end-to-end.
Install a wallet
Any EVM wallet works. We recommend MetaMask or Rabby. The site will detect your wallet automatically once it's installed.
Add Arbitrum Sepolia to your wallet
Click below to add the network. Your wallet will show a confirmation prompt — accept it, then switch to Arbitrum Sepolia in your wallet's network selector.
Add manually instead
- Network name
- Arbitrum Sepolia
- RPC URL
- https://sepolia-rollup.arbitrum.io/rpc
- Chain ID
- 421614
- Currency
- ETH
- Block explorer
- https://sepolia.arbiscan.io
Get testnet ETH for gas
You need a tiny amount of testnet ETH to pay for transactions on Arbitrum Sepolia. The fastest path is a direct Arbitrum Sepolia faucet — pick whichever has the shortest queue:
Or get Sepolia ETH (L1) and bridge to Arbitrum
If the direct faucets are dry, get Ethereum Sepolia ETH first, then bridge to Arbitrum Sepolia.
Then bridge L1 → L2 via the official Arbitrum bridge ↗ (10–15 min for the deposit to land on L2).
Get testnet USDC
Feeds are paid for per byte in USDC. On testnet we use a MockUSDC contract with a public mint function — self-serve any amount.
Approve a USDC allowance
Approve the DataStream settlement contract to pull USDC from your wallet as data is delivered. One-time approval, with a spend cap you set. (The site can also prompt for this on your first subscribe — same result.)
You're ready
Contract addresses
Common problems
- "Insufficient funds for gas" — your wallet's on the wrong network (mainnet?) or you have no testnet ETH yet. Re-check Step 2 and Step 3.
- Subscribed but receiving no data — your USDC balance is below the per-call fee, or the DataStream allowance was revoked. The contract skips delivery silently. Re-check Steps 4 + 5.
- Need help? How it works walks through the full flow.