A nomogram provides a novel solution for assessing the risks of type 2 diabetes among teachers. This is particularly effective when the nomogram incorporates the Healthy Lifestyle Index (HLI) and relevant predictors. In this study, we followed up with a group of teachers from the CLUSTer cohort using RedCap and linked it with the Malaysian National Diabetes Registry. A Cox proportional hazard model was used to determine the predictors associated with T2DM risk in teachers during the follow-up period. We translated our findings into an online interactive nomogram. A total of 3477 teachers were included in the study, of whom 697 (20.0%) were ultimately diagnosed with T2DM. The Cox regression model revealed that HLI and 11 other predictors were significantly associated with diabetes risks among teachers. A nomogram that predicted the risks of T2DM at five, seven, and nine years was developed. Of the 12 predictors, age, fasting blood glucose (FBG), and HLI contributed the most to the total score. Combining the HLI with other predictors in a nomogram allows teachers to assess their T2DM risks and take action to prevent the development of T2DM.