The TOOLSee Saliva Colorimetric RT-LAMP kit offers simple, time-saving, and affordable method including saliva extraction and direct RT-LAMP reaction to detect target gene in form of RNA from saliva via reverse transcription loop-mediated isothermal amplification (RT-LAMP). Saliva is an excellent and non-invasive source of RNA for rapid testing. The saliva extraction is suitable and stable for nucleic acids analysis by simple mix and heating. The extraction is able to be subjected to following analysis by RT-LAMP reactions contains optimized indicator to the RT-LAMP reaction master mix without inhibiting amplification efficiency. The reducing concentration of Mg⁺² in RT-LAMP reaction leading to a color change from violet to sky blue. This Saliva Colorimetric RT-LAMP kit can be used for saliva extracted sample and applies to detection of virus and micro pathogens. The end amplicon of TOOLSee Colorimetric RT-LAMP kit can be verified by agarose gel electrophoresis.