Aim: The aim of this study is to determine the blood glucose levels from gingival crevicular bleeding during routine periodontal examination and to compare its accuracy with finger-prick blood (FPB) using a self-monitoring device during routine dental visits. Materials and methods: A total sample size of n = 80 with group I (gingivitis; n = 40) and group II (periodontitis; n = 40) subjects were included in this study. On periodontal examination, gingival crevicular blood (GCB) was collected and simultaneously FPB was collected from the same patient. A quantity of 2 µL blood from both were analyzed by self-monitoring glucometer (Accu-Chek Active). Results were obtained and statistically analyzed using SPSS software. Result: The mean GCB and FPB glucose levels were 50.98 ± 31.538 and 94.28 ± 41.464, respectively in gingivitis group whereas the mean GCB and FPB were 89.38 ± 46.022 and 160.80 ± 77.761, respectively in periodontitis group. Both the groups suggested a strong positive correlation, where r = 0.924 in gingivitis group and r = 0.808 in periodontitis group. Conclusion: The results from this current study show that GCB collected during diagnostic periodontal examination may also be a reliable source of blood for glucometeric analysis. The glucose levels of crevicular blood can also be a potential risk factor to alter the oral microflora favoring dysbiosis which may lead to the progression of periodontitis. Clinical significance: Diabetes and periodontitis being interlinked with each other influence the oral health and its related treatment. This emphasizes mandatory evaluation of blood glucose levels during regular dental screening. This study evaluates the GCB oozing during periodontal examination that can serve as an alternative source of blood for glucose evaluation, being less traumatic and noninvasive than FPB.