Microsatellites are found to be related with various diseases and widely used in population genetics as genetic markers. However, it remains a challenge to identify microsatellite from large genome and screen microsatellites for primer design from a huge result dataset. Here, we present Krait, a robust and flexible tool for fast investigation of microsatellites in DNA sequences. Krait is designed to identify all types of perfect or imperfect microsatellites on a whole genomic sequence, and is also applicable to identification of compound microsatellites. Primer3 was seamlessly integrated into Krait so that users can design primer for microsatellite amplification in an efficient way. Additionally, Krait can export microsatellite results in FASTA or GFF3 format for further analysis and generate statistical report as well as plotting.