HbA1c calculator

Convert your HbA1c into the average glucose you have had over the last two to three months, using the ADAG study formula endorsed by the American Diabetes Association.

Your HbA1c The percentage shown on your blood test. For example: 7.2

Your estimated average glucose

—mg/dL

Enter your value

Your HbA1c in the other unit: —
The same value, expressed in the international (IFCC) unit.

This is a statistical estimate, not a measurement. Your real glucose varies through the day and this number is its approximate average.

How it is calculated

The formula comes from the ADAG study, published in Diabetes Care in 2008, which compared HbA1c with continuously measured glucose in 507 people:

Average glucose (mg/dL) = 28.7 × HbA1c − 46.7

What your result means

Quick reference
HbA1c	Average glucose	Interpretation
Below 5.7%	Below 117 mg/dL	Normal
5.7 – 6.4%	117 – 137 mg/dL	Increased risk / prediabetes
6.5 – 6.9%	140 – 151 mg/dL	Diabetes range
7.0 – 7.9%	154 – 180 mg/dL	Diabetes range: complications are more than twice as common as below 6
8.0% or above	183 mg/dL or above	Diabetes range: worth reviewing it with your doctor

Important. A single value diagnoses nothing: diagnosis needs confirmation and it is made by your doctor. And your personal HbA1c target is not the same for everyone — it depends on your age, how long you have had it and other conditions. That target is also set by your doctor.

When this number is not reliable

HbA1c measures haemoglobin, so anything that alters your red blood cells alters the result: anaemia, iron or vitamin B12 deficiency, kidney failure, recent transfusions, pregnancy and certain haemoglobin variants. If your meter and your blood test disagree, discuss it with your doctor.

I explain it fully in HbA1c: what it is and how to lower it.

Let's talk

Is your number higher than you expected?

Tell me your case on a free call. I will tell you what real room you have to bring it down.

Which one is you? Pick it and WhatsApp opens with the message already written:

I have prediabetes I have type 2 diabetes I use insulin My blood sugar came back high

Prefer Instagram? Message me on Instagram or tell me right here

First call free · No commitment · Online, anywhere in Spain

Instagram @pabloberna.enf Email pabloberna.enf@gmail.com

Calls are booked in the calendar or in writing: I do not take unscheduled calls. What happens on the first call and how to book it

Please note. This programme supports and complements your medical treatment; it does not replace it. No medication change is made without your doctor.