Is there any good data on blockchain state growth? 

Want to understand how many megabytes or gigabytes per day are being added to full nodes in Eth, Solana etc.

Technowatermelon. Elder Millenial. Building Farcaster. 

nf.td/varun

For Ethereum, the chain state grows around 1-2 GB/day, but it varies based on network activity. Solana's state growth can be more significant due to higher throughput. Tools like Etherscan for Ethereum and Solscan for Solana can provide more granular insights. Always check the latest data sources!