Purpose Many underserved remote locations without specialists would benefit from the ability to quickly and easily share images of radiographs with trained radiologists using WhatsApp messenger. However, there is limited evidence on the role of WhatsApp messenger for sharing chest x-ray (CXR) images to aid diagnosis and management. The objective of the study was to determine the diagnostic accuracy and inter-observer agreement of WhatsApp messenger images of digital CXR compared to viewing on Picture Archiving and Communication System (PACS) monitor. Methods Two pulmonologists reported 400 WhatsApp messenger images of digital CXR each. After a wash period of two weeks, they reviewed the original CXR images on PACS and again reported their findings. Diagnostic agreement was measured using kappa value, diagnostic accuracy was evaluated by sensitivity and specificity. Results The diagnostic agreement between WhatsApp and PACS images for both the readers was high in case of normal CXR (0.84), Pneumonia (0.85) and Active Koch's (0.79) and Old Koch's (0.71). The inter-observer agreement between two readers on WhatsApp images was good in cases of normal chest x-ray (0.74), Active Koch's (0.61) and Pneumonia (0.74) and low in COPD (0.31) and Pleural Effusion (0.28) and Carcinoma Lung (0.40). In terms of radiological lesion, inter-observer agreement between two readers on WhatsApp images was good in terms of the zonal involvement, moderate in case of infiltrates, consolidation, nodules, and fibrosis, fair in cavity, effusion (0.28) and poor in hilar lymphadenopathy (0.14). The sensitivity in the diagnosis of nodules, effusion and hilar lymphadenopathy was Conclusion CXR transmission via WhatsApp is able to identify clinical findings similar to viewing the same image on a PACS monitor in cases of Pneumonia and normal subjects. Active and old Koch's has good comparability whereas; diagnostic agreement is poor in COPD, cavity, pleural effusion and hilar lymphadenopathy, requiring more caution during interpretation.