Sepolia Linea Testnet

An API key generated on LineaScan ​ can be used across all mainnet and testnet explorers.

Similarly, all endpoints and parameter formatting remain the same across testnet explorers, you are only required to change the relevant API endpoint URL as follows.

Network	URL	Documentation
LineaScan	https://api.lineascan.build/api	http://docs.lineascan.build/
Sepolia LineaScan	https://api-sepolia.lineascan.build/api	https://docs.lineascan.build/v/sepolia-lineascan

Source attribution via a backlink or a mention that your app is "Powered by LineaScan APIs" is required except for personal/private usage.