CancerVar is a bioinformatics software tool for clinical interpretation of somatic variants by evidence from AMP/ASCO/CAP/CGC 2017-2019 guideline. The input to CancerVar can be genomic coordinate,dbSNP ID, gene with cDNA change, gene with Protein change, while the output of CancerVar is the interpretation of variants as clinical significance: 'Tier I: Variants of Strong Clinical Significance','Tier II: Variants of Potential Clinical Significance','Tier III: Variants of Unknown Clinical Significance' and 'Tier IV: Benign or Likely Benign Variants', together with detailed evidence.