bookmark tRF2Cancer Facilitates the identification of tRNA-derived small RNA fragments (tRFs) to study their expression in cancers from deep-sequencing data with user-friendly interfaces and time-efficient algorithms. tRF2Cancer provides three useful tools for researchers to investigate tRFs. ‘tRFfinder’ is developed to identify genuine tRF signals from random degradation RNA fragments. One statistical method, the binomial test, is introduced to evaluate the significance of the abundance of sequenced sRNAs distributed on each tRNA. A classification method is subsequently used to annotate the types of tRFs based on their position of origin in pre-tRNA or mature tRNA; the four types of tRFs are tRF-5, tRF-3, tRF-1 and tRF-novel. ‘tRFinCancer’ enables users to inspect the expression of any tRFs in different types of cancers. ‘tRFBrowser’ presents both the sites of origin and the distribution of modification sites of tRFs, including m5C, 2′-O-Me, Ψ and m6A., on their corresponding source tRNA. In addition to cancer samples, tRFfinder can be applied to many samples from different kind of tissue/disease context.