This study reports the observation of single-photon superradiance in perovskite quantum dots (QDs) of the form CsPbX₃ (X = Br, Cl). The research demonstrates that the radiative decay time of these QDs can be significantly reduced, reaching sub-100 picoseconds, which is nearly as short as the exciton coherence time. This phenomenon is attributed to the formation of giant transition dipoles, which enhance the oscillator strength and thus the emission rate. The results highlight the potential of these QDs as ultrabright, coherent quantum light sources, showing that quantum effects such as single-photon emission persist in nanoparticles much larger than the exciton Bohr radius. The study investigates the size-, temperature-, and composition-dependent radiative lifetimes of CsPbBr₃ QDs. It shows that as the size of the QDs increases, the radiative lifetime decreases, indicating enhanced superradiance. The temperature dependence of the radiative lifetime is also explored, revealing that at cryogenic temperatures, the radiative decay is slowed down, which is attributed to increased exciton-phonon coupling and disorder. Composition tuning, such as halide exchange, further enhances the radiative decay rate by increasing the delocalization of the exciton wavefunction. The research also demonstrates that the QDs exhibit quantum properties, including single-photon emission and anti-bunched photon statistics, which are indicative of coherent quantum light sources. The findings provide a comprehensive understanding of the superradiant emission mechanism in perovskite QDs and highlight their potential for applications in quantum technologies. The study is supported by theoretical calculations and simulations, confirming the observed phenomena and providing insights into the underlying physics of excitonic superradiance in these materials.This study reports the observation of single-photon superradiance in perovskite quantum dots (QDs) of the form CsPbX₃ (X = Br, Cl). The research demonstrates that the radiative decay time of these QDs can be significantly reduced, reaching sub-100 picoseconds, which is nearly as short as the exciton coherence time. This phenomenon is attributed to the formation of giant transition dipoles, which enhance the oscillator strength and thus the emission rate. The results highlight the potential of these QDs as ultrabright, coherent quantum light sources, showing that quantum effects such as single-photon emission persist in nanoparticles much larger than the exciton Bohr radius. The study investigates the size-, temperature-, and composition-dependent radiative lifetimes of CsPbBr₃ QDs. It shows that as the size of the QDs increases, the radiative lifetime decreases, indicating enhanced superradiance. The temperature dependence of the radiative lifetime is also explored, revealing that at cryogenic temperatures, the radiative decay is slowed down, which is attributed to increased exciton-phonon coupling and disorder. Composition tuning, such as halide exchange, further enhances the radiative decay rate by increasing the delocalization of the exciton wavefunction. The research also demonstrates that the QDs exhibit quantum properties, including single-photon emission and anti-bunched photon statistics, which are indicative of coherent quantum light sources. The findings provide a comprehensive understanding of the superradiant emission mechanism in perovskite QDs and highlight their potential for applications in quantum technologies. The study is supported by theoretical calculations and simulations, confirming the observed phenomena and providing insights into the underlying physics of excitonic superradiance in these materials.