Diabetes and prediabetes risk
Japanese Diabetes Risk Score
A short score built from the yearly health checkups of Japanese company workers to estimate the chance of type 2 diabetes in the next 3 years. It works without a blood test; if you have a recent fasting glucose or HbA1c result, add it for a sharper estimate.
Your answers
Based on the published Japanese workers' diabetes risk score, in our own words. Nothing you enter leaves this page.
Measured standing, at the level of your navel, as in the study.
Optional: recent blood test
Leave these empty if you do not know them. Use results from a test taken without diabetes medicine.
What you will see
Your score, whether it reaches the developers' cut point, your estimated chance of type 2 diabetes within 3 years and the points behind it.
Educational only, not medical advice. A risk estimate, not a diagnosis.
Source
Nanri A et al., PLoS One 2015 (open access): points from Table 3 of the paper; 3-year risk by score from Table 5 as corrected by the authors in 2018.
Validated in
Built in 24,950 and checked in 12,466 employees aged 30 and older of eight companies in Japan who had health checkups in 2008 or 2009 and again 3 years later (Japan Epidemiology Collaboration on Occupational Health Study). Diabetes was found by fasting or random glucose, HbA1c or diabetes treatment at later checkups.
Limits
About 86% of the people in the study were men, all were employed and all lived in Japan, so the score may fit women, retired people and other groups less well. It looks only 3 years ahead. Family history and exercise were not part of the checkups, so the score leaves them out. The version without blood tests was somewhat less well calibrated than the version with both blood tests. People who already have diabetes should not use it.
Japanese score, Korean score, FINDRISC or the US test?
The Japanese score is built for adults from 30 years old and predicts new type 2 diabetes over the next 3 years. It also lets you add a fasting glucose or HbA1c result (Nanri 2015). The Korean diabetes risk score (Lee 2012) and the Chinese Diabetes Risk Score (Zhou 2013) look for diabetes you may already have without knowing it. The FINDRISC calculator comes from Finland and looks 10 years ahead (Lindström 2003), and the US type 2 diabetes risk test was built in US survey data (Bang 2009). Pick the one built closest to where you live and who you are.
The points
The study gave each answer points in four versions of the score: with no blood test, with fasting glucose, with HbA1c, or with both. The calculator picks the version that matches what you enter (Nanri 2015).
| Factor | Answer | No blood test | + glucose | + HbA1c | + both |
|---|---|---|---|---|---|
| Sex | Male | 2 | 0 | 2 | 1 |
| Age | 40 to 49 / 50 to 59 / 60 or older | 2 / 4 / 4 | 2 / 2 / 3 | 2 / 2 / 2 | 2 / 2 / 2 |
| BMI | 21 to 22.9 / 23 to 24.9 / 25 to 26.9 / 27 to 28.9 / 29 or more | 2 / 2 / 3 / 3 / 4 | 1 / 2 / 2 / 2 / 3 | 1 / 2 / 2 / 2 / 2 | 0 / 1 / 2 / 2 / 2 |
| Waist | Men 90 cm or more, women 80 cm or more | 2 | 1 | 1 | 1 |
| Smoking | Smokes now | 2 | 2 | 1 | 2 |
| High blood pressure | Yes | 2 | 1 | 2 | 2 |
| Fasting glucose | 100 to 109 / 110 to 125 mg/dL | 4 / 5 | 3 / 5 | ||
| HbA1c | 5.6 to 5.9% / 6.0 to 6.4% | 4 / 5 | 3 / 5 | ||
| Highest possible score | 16 | 15 | 15 | 20 |
Women, ages 30 to 39, a BMI under 21, a fasting glucose under 100 mg/dL and an HbA1c under 5.6% score 0. Points from Table 3 of the paper (Nanri 2015). High blood pressure meant 140/90 mmHg or more, or taking blood pressure medicine. HbA1c is in the international (NGSP) units used in the US (Nanri 2015). Fasting glucose in mmol/L times 18 gives mg/dL.
Example: a 52-year-old man with a BMI of 26 and a waist of 92 cm who does not smoke and has normal blood pressure scores 2 (male) + 4 (age) + 3 (BMI) + 2 (waist) = 11 with no blood test. The corrected table puts the 3-year chance of diabetes at a score of 11 at 9.0% (Nanri 2015).
What the score means
The authors turned each score into an estimated chance of developing type 2 diabetes within 3 years. In 2018 they corrected that table, because the first version showed observed rather than estimated figures; the calculator uses the corrected numbers (Nanri 2015). With no blood test, the estimate runs from 0.5% at a score of 0 to 27.7% at 16. With both blood tests it runs from 0.1% at 0 to 74.2% at 20 (Nanri 2015).
The cut points that best balanced finding future cases against flagging people who stayed free of diabetes were 9 with no blood test, 7 with fasting glucose, 10 with HbA1c and 11 with both. With no blood test, a score of 9 or more picked up 61% of the people who went on to get diabetes, and 71% of those who did not scored under 9 (Nanri 2015). The score with no blood test separated the two groups with an area under the curve of 0.72 (0.73 in the checking group); adding both blood tests raised it to 0.89 (0.88) (Nanri 2015).
What to do with your result
A score at or above the cut point is a reason to ask your doctor about a blood sugar test and about steps that lower diabetes risk, such as weight loss and more activity. A score below it does not rule diabetes out. If your fasting glucose is 126 mg/dL or more, or your HbA1c is 6.5% or more, the calculator will not score you, because those values are in the diabetes range and the study left such people out (Nanri 2015). In the US, the US Preventive Services Task Force recommends screening for prediabetes and type 2 diabetes in adults aged 35 to 70 who have overweight or obesity (USPSTF 2021), whatever any risk score says.
See also the Korean diabetes risk score, the Peruvian diabetes risk score, the Chinese Diabetes Risk Score, the Indian Diabetes Risk Score, the FINDRISC calculator, the type 2 diabetes risk test, the A1C to average glucose converter, prediabetes ranges and next steps, when to get tested for diabetes and the BMI calculator.
Sources
- Nanri A, Nakagawa T, Kuwahara K, et al. Development of risk score for predicting 3-year incidence of type 2 diabetes: Japan Epidemiology Collaboration on Occupational Health Study. PLoS One. 2015;10(11):e0142779. doi:10.1371/journal.pone.0142779. PMID 26558900. Correction: PLoS One. 2018;13(6):e0199075 (corrected Table 5). pmc.ncbi.nlm.nih.gov/articles/PMC4641714/
- US Preventive Services Task Force. Screening for Prediabetes and Type 2 Diabetes: Recommendation Statement. JAMA. 2021;326(8):736-743. www.uspreventiveservicestaskforce.org/uspstf/recommendation/screening-for-prediabetes-and-type-2-diabetes
- Lee YH, Bang H, Kim HC, Kim HM, Park SW, Kim DJ. A simple screening score for diabetes for the Korean population: development, validation, and comparison with other scores. Diabetes Care. 2012;35(8):1723-1730. doi:10.2337/dc11-2347. PMID 22688547. pmc.ncbi.nlm.nih.gov/articles/PMC3402268/
- Zhou X, Qiao Q, Ji L, et al. Nonlaboratory-based risk assessment algorithm for undiagnosed type 2 diabetes developed on a nation-wide diabetes survey. Diabetes Care. 2013;36(12):3944-3952. doi:10.2337/dc13-0593. PMID 24144651. pmc.ncbi.nlm.nih.gov/articles/PMC3836161/
- Lindström J, Tuomilehto J. The diabetes risk score: a practical tool to predict type 2 diabetes risk. Diabetes Care. 2003;26(3):725-731. PMID 12610029. pubmed.ncbi.nlm.nih.gov/12610029/
- Bang H, Edwards AM, Bomback AS, et al. Development and validation of a patient self-assessment score for diabetes risk. Ann Intern Med. 2009;151(11):775-783. doi.org/10.7326/0003-4819-151-11-200912010-00005
Written and maintained by the uncovermyrisk.com editorial team. We do not have a medical reviewer; every claim links to its primary source above. Last reviewed: 2026-11-01. Spotted an error? See About.