An efficient, compact 970 nm laser diode end-pumped Er:YSGG laser operating in continuous and pulsed modes is reported. In the continuous-wave regime, an output power of ∼1.6 W mid-infrared laser with 2.79 μm wavelength is obtained, corresponding to an optical efficiency of 19.6% and slope efficiency of 25.3%. In the pulsed regime, an energy of 144 mJ and a slope efficiency of 43.5% are achieved with a 30 at. % Er:YSGG crystal in 3×3×5 mm3 dimensions. The high-pulse energy and the high efficiency indicate that Er:YSGG lasers can potentially be used for blood sampling.