I propose a novel theoretical framework that establishes a fundamental upper bound on the rate of biological evolution, which I term the Darwin Limit. This concept draws an analogy to the Planck Time in physics, serving as a minimal temporal unit that constrains the speed at which adaptive genetic changes can occur without compromising genomic stability. By integrating principles from information theory, thermodynamics, and evolutionary biology, I develop a mathematical model linking informational potential, genetic entropy, and evolutionary time, providing a quantitative measure for the maximal adaptive velocity a biological system can achieve. I demonstrate that, as the entropy associated with genetic variation increases, the effective rate of adaptive evolution is inherently limited, creating a natural ceiling to the speed of evolution. This ceiling explains why, despite strong selective pressures, biological systems cannot evolve arbitrarily fast, and why phenomena such as punctuated equilibrium or evolutionary stasis emerge. Furthermore, I explore the implications of the Darwin Limit for synthetic biology and artificial evolutionary systems, suggesting that informational and entropic constraints also bound the speed of adaptation in engineered or computationally evolving entities. By framing evolution as a process governed by thermodynamic-information constraints, the Darwin Limit provides a unifying theoretical lens to understand the interplay between time, entropy, and adaptive potential across natural and artificial evolutionary systems. Ultimately, this framework lays the groundwork for quantitative predictions of evolutionary dynamics, opening avenues for experimental verification and establishing the Darwin Limit as a potential cornerstone in theoretical biology and evolutionary physics.