We study a fragmentation problem where an initial object of size x is broken into m random pieces provided x > x0 where x0 is an atomic cut-off. Subsequently the fragmentation process continues for each of those daughter pieces whose sizes are bigger than x0. The process stops when all the fragments have sizes smaller than x0. We show that the fluctuation of the total number of splitting events, characterized by the variance, generically undergoes a nontrivial phase transition as one tunes the branching number m through a critical value m = mc. For m < mc, the fluctuations are Gaussian where as for m > mc they are anomalously large and non-Gaussian. We apply this general result to analyze two different search algorithms in computer science. [5]. In this paper we consider a problem where an object of initial size (or length) x is first broken into m random pieces of sizes x i = r i x with m i=1 r i = 1 provided the initial size x > x 0 where x 0 is a fixed 'atomic' threshold. At the next stage, each of those m pieces with sizes bigger than x 0 is further broken into m random pieces and so on. Clearly the process stops after a finite number of fragmentation or splitting events when the sizes of all the pieces become less than x 0 . This problem and its close cousins have already appeared in numerous contexts including the energy cascades in turbulence [6], rupture processes in earthquakes [7], stock market crashes [8], binary search algorithms [9-11], stochastic fragmentation [12] and DNA segmentation algorithms [13]. It therefore comes as somewhat of a surprise that there is a nontrivial phase transition in this problem as one tunes the branching number m through a critical value m = m c .In this Letter we study analytically the statistics of the total number of fragmentation events n(x) up till the end of the process as a function of the initial size x. We show that, while the average number of events µ(x) always grows linearly with x for large x, the asymptotic behavior of the variance ν(x), characterizing the fluctuations, undergoes a phase transition at a critical value m = m c ,The exponent θ is nontrivial and increases monotonically with m for m ≥ m c starting at θ(m = m c ) = 1/2 and the amplitude of the leading x 2θ term has log-periodic oscillations for m ≥ m c . This signals unusually large fluctuations in n(x) for m > m c . The full distribution of n(x) also changes from being Gaussian for m < m c to non-Gaussian for m > m c . This phase transition is rather generic for any fragmentation problem with an 'atomic' threshold. However the critical value m c and the exponent θ are nonuniversal and depend on the distribution function of the random fractions r i 's. In this Letter we establish this generic phase transition and then calculate explicitly m c and θ for two special cases with direct applications in computer science.In this fragmentation problem with a fixed lower cut-off x 0 , one first breaks the initial piece of length x provided x > x 0 into m pieces of sizes x i = r i x. The sizes of each of...