The detection of single nucleotide polymorphisms by PCR is necessary for many types of genetic analysis, from mapping genomes to tracking specific mutations. This technique is most commonly used when polymorphisms alter restriction endonuclease recognition sites. Here we describe a web-based program, dCAPS Finder 2.0, that facilitates the design of mismatched PCR primers to create or remove a restriction endonuclease recognition site relative to the polymorphism being analyzed. The detection of single nucleotide polymorphisms by PCR is necessary for many types of genetic analysis, from mapping genomes to tracking specific mutations. A web-based program, dCAPS Finder 2.0, facilitates the design of mismatched PCR primers to aid such analysis.