BACKGROUND: Blood pressure (BP) is a common clinical measurement, now increasingly done at home. Media websites often display images of BP measurement to represent clinical medicine, but many images deviate from guidelines, potentially creating misperceptions on how measurement should be performed. We evaluated the accuracy of BP measurement images online according to the 2023 International Consensus on Standardized Clinic BP Measurement. METHODS: We evaluated the first ≈100 images from each of 11 major stock photo websites. Two independent reviewers assessed each image, resolving disagreements through discussion. Only visible accuracy aspects were scored. RESULTS: Only 14% of images (N=1106) were accurate on all criteria, ranging from 7% at Flickr and Freepik to 28% at iStock. Photo settings included 63% clinical and 37% home-based; 73% by healthcare providers, 24% by patients, and 3% other settings. Images were penalized for the following guideline deviations: back unsupported (73%), forearm not resting on a surface (55%), manual and not electronic device (52%), feet not flat on the floor (36%), doctor or observer talking/laughing (23%), mid-arm not at heart level (19%), patient talking/laughing (18%), legs crossed (13%), cuff on clothing (12%), and patient not sitting (5%). Accuracy levels differed by setting (clinical 8% versus home 25%, P<0.001) and assessors (self 35%, healthcare provider 7%, and other people 13%; P<0.001). CONCLUSIONS: Only 1 in 7 online stock photo images of BP measurement align with clinical guidelines. Media houses, website developers, and the public should be educated on appropriate measurement techniques to ensure accurate BP measurement in the clinic and at home.