KuantiBurn is an advanced laser analysis tool that quantifies the effects of spatial hole burning in optical cavities, offering a quick way to assess instability risks and mode competition behavior. By combining user-provided cavity parameters with a physics-inspired model, the app delivers an Instability Index and a Mode Beating Probability that help users visualize the stability of their design. Along with these results, KuantiBurn includes practical recommendations for cavity adjustments to reduce SHB, making it a valuable resource for scientists, engineers, and students seeking to optimize laser performance and stability in both research and applied optics.