According to the data shared by crypto data analyst Kofi on the X platform, Base's on-chain profit reached $6.98 million in May, ranking first among all L2 chains. Optimism ranked second, achieving $1.57 million in on-chain profit, Scroll ($1.35 million), Arbitrum ($802,000) and Linea ($612,000) ranked 3rd to 5th. Note: On-chain profit = L2 Gas fee income - L1 batch release and proof verification costs.