Which tests diagnose diabetes? Fasting, PP, random sugar and HbA1c
Medically reviewed by Dr. N. S. Santosh Varma, MBBS, FIM, FIDM, FICCM · Reg. APMC/FMR 112686 · Updated the day of publishing
Diabetes is diagnosed with blood sugar tests. Commonly used cut-offs: fasting sugar 126 mg/dL or above, 2-hour sugar after 75 g glucose 200 or above, HbA1c 6.5% or above, or a random sugar of 200 or above with symptoms. Fasting sugar of 100–125 or HbA1c of 5.7–6.4% suggests prediabetes. A doctor confirms the diagnosis.
Diagnostic cut-offs
| Test | Normal | Prediabetes | Diabetes |
|---|---|---|---|
| Fasting blood sugar (mg/dL) | below 100 | 100–125 | 126 or above |
| 2-hour sugar after 75 g glucose (mg/dL) | below 140 | 140–199 | 200 or above |
| HbA1c (%) | below 5.7 | 5.7–6.4 | 6.5 or above |
| Random blood sugar (mg/dL) | — | — | 200 or above with symptoms |
Without symptoms, a doctor usually repeats the test before confirming diabetes.
Who should get tested
- Adults over 30, especially with a family history
- People who are overweight or inactive
- People with high blood pressure or high cholesterol
- Women who had diabetes in pregnancy
- Anyone with excess thirst, frequent urination or weight loss
Is it included in YIRA's checkup?
YIRA's 70-test checkup includes a random blood sugar test as a first screen. Fasting, post-meal and HbA1c tests can be added on a doctor's advice; see HbA1c test and normal blood sugar levels.
A YIRA Family Health Plan includes a 70-test full body checkup at home for one registered member, a doctor consultation for the family, a review of an elder's past reports, and dental and eye check-ups. Essential ₹999 a year (up to 4 family members registered); Complete ₹1,299 a year (up to 8, with ₹5 lakh accident cover for the buyer).
70-test checkup at home plus family care, from ₹999 a year
Essential ₹999 (one 70-test checkup, up to 4 family members registered) · Complete ₹1,299 (up to 8, with ₹5 lakh accident cover). Doctor consultation, dental and eye check-ups included. Pay after sample collection.
Frequently asked questions
Which is the best test for diabetes?
Each has a role. HbA1c needs no fasting and shows a 3-month average; fasting sugar and the glucose tolerance test are also standard. Your doctor chooses.
Can diabetes be diagnosed with one test?
With clear symptoms and a very high value, yes. Otherwise doctors usually repeat or confirm with a second test.
How often should I check for diabetes?
If you are at risk, usually once a year, or as your doctor advises.
Related
Medically reviewed by Dr. N. S. Santosh Varma (MBBS, FIM, FIDM, FICCM; APMC/FMR 112686). Prepared by the YIRA health team · Last updated 1 October 2026. This page is general health information, not medical advice or a diagnosis. Reference ranges differ between labs; always discuss your results with a doctor. In an emergency, call 108 or go to the nearest hospital.