A free A1C calculator that turns A1C into average glucose and back, with the CDC's ranges.
Turn an A1C result into average glucose, or the other way, and see where it sits in the CDC's ranges.
Your numbers
A1C is the percent your lab report gives. Average glucose works in mg/dL (US) or mmol/L (most other countries).
Your result
Fill in the fields above to see your result.
These calculators give general estimates for healthy adults, not medical advice. Talk to your doctor before you change how you eat or train, especially if you're pregnant, take medication or have a health condition.
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This free A1C calculator turns an A1C result into your estimated average glucose, or an average glucose into an A1C, and shows where it sits in the CDC's ranges.
It works in mg/dL and mmol/L, so it reads a lab report from any country.
I built it because an A1C percent is hard to picture, and the average glucose behind it is the number people know from a meter.
Here's what A1C measures, the formula behind it, and what the ranges mean. It's general information, not a diagnosis.
TL;DRKey takeaways
What is an A1C calculator?
An A1C calculator turns an A1C percent into the average blood sugar it stands for, and back.
As the CDC puts it, the A1C test measures your average blood sugar level over the past 2 or 3 months.
How A1C becomes average glucose
The formula comes from the A1C-Derived Average Glucose (ADAG) study, published in Diabetes Care in 2008, as NGSP, the program that standardizes A1C tests, publishes it.
| A1C | Average glucose |
|---|---|
| 5% | 97 mg/dL (5.4 mmol/L) |
| 7% | 154 mg/dL (8.6 mmol/L) |
| 10% | 240 mg/dL (13.4 mmol/L) |
The CDC's ranges
The CDC gives 3 ranges for A1C.
A worked example
Here's the example the calculator loads: an A1C of 6.2%.
28.7 × 6.2 − 46.7 = 131 mg/dL, or 7.3 mmol/L. That's in the CDC's prediabetes range.
What A1C can't tell you
A1C is an average, so it hides the highs and lows of a day.
- Treating a calculator result as a diagnosis
- Comparing a home meter reading to an A1C from a single day
- Changing medication from a number here instead of with your doctor
Who is the A1C calculator for?
It's for anyone reading a lab report or tracking their health, and these tools help around it.
- BMI calculator – for weight and height
- Calorie calculator – for a daily calorie target
- Macro calculator – for protein, fat and carbs
Bring your numbers to your doctor, and ask what they mean for you.
Plan your health with your AI
Take your numbers further in
A1C Calculator FAQs
Questions about the a1C calculator? Here's what to know.
An A1C calculator turns an A1C percent into an estimated average glucose, and back.
Below 5.7%, by the CDC's ranges.
5.7% to 6.4%, by the CDC's ranges.
6.5% or above, by the CDC's ranges.
Only a doctor diagnoses diabetes, from lab tests.
About 154 mg/dL, or 8.6 mmol/L.
By the ADAG study's formula: 28.7 × A1C − 46.7 mg/dL.
The past 2 or 3 months, as the CDC describes it.
Yes, it's free with no sign-up.
It runs in your browser, and your numbers stay on your device.
I did.
I'm Navid Moazzez, and I made the A1C calculator as one of my free tools on navid.me.
More about me.
Navid Moazzez
AI business strategist & AI OS builder
Navid Moazzez helps creators and founders master AI and build their own AI Operating System (AI OS) to automate their business and life.
Navid.me is reader-supported. When you buy through links on this site, I may earn an affiliate commission. Learn more.
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