WannierTools is an open-source software package designed for the investigation of novel topological materials. It operates within the tight-binding framework, utilizing data generated by the Wannier90 software. The tool enables the classification of topological phases by calculating the Wilson loop and determining surface state spectra detectable via ARPES and STM experiments. It identifies Weyl/Dirac points and nodal line structures, calculates Berry phase and Berry curvature within the Brillouin zone. The software is written in Fortran 90 and is parallelized using MPI, offering efficient performance. It is user-friendly and requires only an input file with system parameters and a TB model in Wannier90_hr.dat format. WannierTools can calculate topological numbers such as Z2 and Chern numbers, and it helps identify Weyl/Dirac points or nodal line structures in metallic systems. It also provides functions for studying electronic properties of slab and ribbon systems, Berry curvature, and Berry phase in nodal-line systems. The paper introduces WannierTools, detailing its methods, capabilities, installation, and usage. It demonstrates the application of WannierTools on the topological material HfPtGe, showing how it can be used to explore new topological phases. The software is capable of analyzing the bulk topology of materials, including the calculation of Z2 topological indices, and studying surface states related to the bulk topology. It can generate surface state spectra, analyze spin textures, and determine energy gap shapes. The tool is efficient and suitable for high-throughput searches of new topological materials. The paper concludes by highlighting the importance of WannierTools in the study of topological materials and its potential for future research.WannierTools is an open-source software package designed for the investigation of novel topological materials. It operates within the tight-binding framework, utilizing data generated by the Wannier90 software. The tool enables the classification of topological phases by calculating the Wilson loop and determining surface state spectra detectable via ARPES and STM experiments. It identifies Weyl/Dirac points and nodal line structures, calculates Berry phase and Berry curvature within the Brillouin zone. The software is written in Fortran 90 and is parallelized using MPI, offering efficient performance. It is user-friendly and requires only an input file with system parameters and a TB model in Wannier90_hr.dat format. WannierTools can calculate topological numbers such as Z2 and Chern numbers, and it helps identify Weyl/Dirac points or nodal line structures in metallic systems. It also provides functions for studying electronic properties of slab and ribbon systems, Berry curvature, and Berry phase in nodal-line systems. The paper introduces WannierTools, detailing its methods, capabilities, installation, and usage. It demonstrates the application of WannierTools on the topological material HfPtGe, showing how it can be used to explore new topological phases. The software is capable of analyzing the bulk topology of materials, including the calculation of Z2 topological indices, and studying surface states related to the bulk topology. It can generate surface state spectra, analyze spin textures, and determine energy gap shapes. The tool is efficient and suitable for high-throughput searches of new topological materials. The paper concludes by highlighting the importance of WannierTools in the study of topological materials and its potential for future research.