Generative AI is part of daily work, but few of us know what it costs the planet: electricity, CO2, the water used for cooling and the hardware behind every request. This talk is a practical guide to frugal AI for frontend and product teams. We start with what the footprint actually is, why published estimates vary so widely, and what you can realistically measure yourself: tokens sent, calls made and calls avoided. Then the actions. Decide which requests can be answered on the device instead, using Chrome's built-in Gemini Nano and small models in the browser. Route the rest through a hybrid setup so a server model is the exception, not the default. Trim what you do send with tighter prompts, caching and response limits. We also cover the rebound effect, where cheaper AI simply leads to more AI use, and why frugality needs a budget, not just good intentions. Live demos show features running with zero API calls. You will leave with a decision checklist for on-device, hybrid or server, and a way to make the case to the people who pay the bill.