Best way to quickly check Solana price and calculate my portfolio value?

I've been building my Solana position and I'm always trying to figure out what my bags are worth in dollars. Most price sites show the per-coin rate but I have to do the math myself, and with SOL moving around it's annoying. Is there a simple tool where I can just enter my SOL amount and instantly see the USD value? Also would be useful to do the reverse – if I want to buy more, I'd like to know how much SOL I'd get for say $100. Any recommendations?