Despite the importance of cell characterization and identification for diagnostic and therapeutic applications, developing fast and label-free methods without (bio)-chemical markers or surface-engineered receptors remains challenging. Here, we exploit the natural cellular response to mild thermal stimuli and propose a label- and receptor-free method for fast and facile cell characterization. Cell suspensions in a dedicated sensor are exposed to a temperature gradient, which stimulates synchronized and spontaneous cell-detachment with sharply defined time-patterns, a phenomenon unknown from literature. These patterns depend on metabolic activity (controlled through temperature, nutrients, and drugs) and provide a library of cell-type-specific indicators, allowing to distinguish several yeast strains as well as cancer cells. Under specific conditions, synchronized glycolytic-type oscillations are observed during detachment of mammalian and yeast-cell ensembles, providing additional cell-specific signatures. These findings suggest potential applications for cell viability analysis and for assessing the collective response of cancer cells to drugs. This project was funded by the KU Leuven project C14/15/066 “Smart Cellular Scaffolds”, the Research Foundation Flanders FWO, project G.0791.16N “Utilizing interfacial impedance- and heat-transfer phenomena in advanced monitoring- and switching devices,” and the bilateral FWO Flanders—FWF Austria project “Simultaneous multiparametric readout for low-cost nanoparticle sensors”. P.V.B. acknowledges funding from Hercules AKUL/11/37 and FWO G.0929.15. T.M. acknowledges funding from FWO I000321N project. The authors thank Prof. Kasper Eersels (Maastricht University, The Netherlands), Prof. Jef Hooyberghs (VITO, Belgium), and Prof. Ward De Ceuninck (Hasselt University, Belgium) for stimulating discussions. The authors appreciate Dr. Peter Cornelis, Dr. Kuo Zhong, Dr. Gideon Wackers, Dr. Celien Lismont, Dr. Wouter Van Genechten, Drs. Christiana Adebayo, and Mr. Werner Neefs (all of KU Leuven, Belgium), as well as Dr. Heiko Iken (FH Aachen) for their technical assistance.