Dye-based detection (e.g., SYBR^® Green) requires only addition of PCR primers, making it a cost-effective qPCR option. However, the intercalating dye will detect any dsDNA produced in the reaction. Therefore, off-target and non-template amplification (NTC) can be observed for some primer sets, resulting in inaccurate quantification. Denaturation (melt) curves performed after the PCR can be used to distinguish between correct and nonspecific products. Additionally, only a single amplicon can be measured in a dye-based qPCR with no ability to perform multiplex reactions.

Probe-based detection requires designing and obtaining a sequence-specific fluorescently-labeled probe oligonucleotide in addition to typical PCR primers. This increases assay costs, but probe-based qPCR experiments benefit from extreme specificity and are unlikely to result in inaccurate quantification due to NTC amplification. Multiplex reactions are possible with probes, as different amplicons can be designed with unique fluorophores according to the optical capabilities of the qPCR instrument.