A hybrid Bitcoin–Ethereum Layer 2 testnet, BOB Sepolia provides EVM compatibility, ETH gas, low fees, and fast confirmations for cross-ecosystem dApp development.
BOB Sepolia is the public testnet for BOB (Build on Bitcoin), an EVM-compatible L2 that uses ETH as gas and mirrors mainnet parameters on Ethereum Sepolia. It’s used to test cross-chain bridges, L1↔L2 messaging, and Bitcoin-integrated features without real funds. Typical performance: ~2s block time, sub-cent average fees, and hundreds of TPS; activity is developer-focused with periodic load during test events.
Unlike generic EVM testnets, BOB Sepolia pairs OP Stack EVM compatibility with a Bitcoin-aligned design, targeting BTC-secured economics (e.g., via Babylon) while retaining ETH gas and full Ethereum tooling. Compared with Sepolia L1 (~12s blocks, ~15 TPS), BOB Sepolia delivers L2 latency (~2s blocks) and sub-cent fees, enabling faster bridge confirmations and large-scale QA. This hybrid Bitcoin–Ethereum focus plus low-cost, high-throughput execution makes it distinct for building Bitcoin-aware dApps.
BOB Sepolia uses ETH as the gas token for transaction fees. You can obtain ETH by bridging from other chains or purchasing using thirdweb Bridge, or through faucets (for testnet).
To bridge ETH to BOB Sepolia, connect your wallet to thirdweb bridge, select your source chain, choose the token you want to bridge, select BOB Sepolia as the destination, enter the amount, and confirm the transaction. The bridge will handle the cross-chain transfer instantly.
To build on BOB Sepolia you can use thirdweb, which provides an easy way to build, monetize and scale your apps, games or agents. You can find detailed guides and documentation on https://portal.thirdweb.com to get started quickly.
To add BOB Sepolia to your wallet, you can connect your wallet and click on [Add to Wallet] button at the top of the page. Alternatively, you can add the network manually using the RPC URL and chain details and add it to your wallet's network settings.
To send ETH on BOB Sepolia, ensure your wallet is connected to the BOB Sepolia network, enter the recipient's address, specify the amount of ETH to send, review the gas fee, and confirm the transaction in your wallet.