Free tools

Calculators

Free, no-signup tools that turn the research into a number for your situation. No email, no catch.

AI Subscription vs API Cost

At your usage, is a $20 AI plan or the pay-per-token API cheaper? Compares ChatGPT, Claude, Gemini, and Grok.

Pick your devices and see the upfront cost range, DIY vs pro, and the monthly and 5-year ongoing cost.

Estimate how much a smart thermostat, plugs, and lighting save on your bill each year, and the payback time.