What free tools saved your life when you were starting with $0 budget?

Long-time reader, first-time poster. I’m launching my first small site on a shoe-string budget, so I can't afford $100/month software subscriptions just yet. What are some essential free tools, browser extensions, or sites you still rely on even now?

Google Search Console was probably the most valuable free tool when I was starting out because it provided actionable data about search volume and traffic. I would add Sheets and Docs since they were essential in keeping track of things without spending a dime. Looking back, access to data was significantly more important than any paid tools.