The production and disposal of short-term-use electronics pose significant environmental implications due to intensive resource use, hazardous processing, and growing electronic waste. We present the synthesis of a bio-based carbon ink as a sustainable functional material for printed electronics, demonstrating its application potential as temperature sensor and heater on uncoated paper substrate for the realization of fully bio-based and potentially biodegradable devices. For temperature sensing, a thermal coefficient of resistance of –2.3 * 10–3 K−1 was obtained, while the heating element exhibited temperatures of up to 160 °C at 0.5 W.