Over the past few decades, the prevalence of hypervirulent Klebsiella pneumoniae (hvKp) in the Asia-Pacific region, notably associated with community-acquired pyogenic liver abscesses, has been alarming. Most existing hvKp detection methods are time-consuming and rely on expensive equipment, which is particularly problematic in resource-limited settings. Thus, there is an urgent need for convenient, rapid, and cost-effective approaches to the identification and quantification of hvKp. In this study, we developed a CRISPR Cas12a-based smartphone-assisted colorimetric quantitative platform (Cas12a-SACQP), a portable platform enabling visible nucleic acid detection and analysis via a smartphone application with on-site detection capability. We applied Cas12a-SACQP to detect multiple virulence genes of hvKp, including rmpA, iroB, iucA, and peg-344. The limits of detection (LODs) for these genes were 2.42 CFU/mL for rmpA, 2.33 CFU/mL for iroB, 1.72 CFU/mL for iucA, and 2.83 CFU/mL for peg-344, respectively. We simultaneously tested Klebsiella pneumoniae clinical strains from various samples (ear discharge, sputum, and blood) for these virulence genes. Compared with conventional PCR identification and real-time PCR, Cas12a-SACQP effectively differentiates classical Klebsiella pneumoniae (cKp) from hvKp from these diverse clinical sources. Furthermore, the entire Cas12a-SACQP workflow can be performed using portable devices, and the results can be rapidly visualized via a smartphone. This platform, therefore, holds substantial potential for rapid and quantitative detection of clinical pathogens in resource-constrained environments.