Background: Tobacco use poses various health risks, including respiratory and cardiovascular diseases. Aim: This study assesses oxygen saturation, carboxyhemoglobin, and carbon monoxide levels in smokers versus nonsmokers. Methods: Participants abstained from smoking for 3 hours before measuring exhaled carbon monoxide and carboxyhemoglobin. After holding their breath for 15 s, they exhaled into a breath analyzer. Oxygen saturation was measured via pulse oximeter on the right index finger. Results: Significant differences were observed between cigarette smokers, Beedi smokers, and nonsmokers for carbon monoxide and carboxyhemoglobin levels (P = 0.001). Beedi smokers also had higher levels than nonsmokers (P = 0.001). ANOVA showed significant differences across groups (P = 0.001). Carboxyhemoglobin correlated positively with carbon monoxide and negatively with oxygen saturation. Conclusion: Oxygen saturation, carboxyhemoglobin, and carbon monoxide are effective chairside biomarkers for smoking status, providing immediate feedback on harmful effects. © 2024 Elsevier B.V., All rights reserved.