Blood Sugar Converter
Convert blood glucose levels between mg/dL and mmol/L units with clinical interpretation
Convert Blood Glucose Units
Enter your glucose reading in the selected unit
Conversion Formula
mg/dL to mmol/L: Divide by 18
mmol/L to mg/dL: Multiply by 18
1 mmol/L = 18 mg/dL
Conversion Results
Blood Glucose Reference Ranges
Normal Ranges
- • Fasting: 70-100 mg/dL (3.9-5.5 mmol/L)
- • After meals: <140 mg/dL (<7.8 mmol/L)
- • Random: 79-110 mg/dL (4.4-6.1 mmol/L)
Diabetes Ranges
- • Pre-diabetes: 100-125 mg/dL (5.6-6.9 mmol/L)
- • Diabetes: ≥126 mg/dL (≥7.0 mmol/L) fasting
- • Random diabetes: ≥200 mg/dL (≥11.1 mmol/L)
Common Conversion Examples
Normal Fasting
90 mg/dL = 5.0 mmol/L
Healthy fasting glucose
Pre-diabetes
110 mg/dL = 6.1 mmol/L
Elevated glucose level
Diabetes
200 mg/dL = 11.1 mmol/L
Diabetic range glucose
Understanding Units
mg/dL
Milligrams per deciliter - commonly used in the United States and continental Europe
mmol/L
Millimoles per liter - international standard unit used in most countries
Key conversion: 1 mmol/L = 18 mg/dL
Medical Disclaimer
This calculator is for educational purposes only. Always consult with healthcare professionals for medical advice, diagnosis, or treatment. Do not use this tool as a substitute for professional medical care.
When to Check Blood Sugar
Fasting (8+ hours without food)
2 hours after meals
Before bedtime
When feeling symptoms
As directed by healthcare provider
Understanding Blood Glucose Measurement
What is Glycemia?
Glycemia refers to the presence and concentration of glucose in the blood. Blood glucose levels are measured to assess how well the body processes sugar and to diagnose conditions like diabetes and hypoglycemia.
Types of Blood Glucose Tests
- •Fasting glucose: Measured after 8+ hours without food
- •Random glucose: Measured at any time regardless of meals
- •Postprandial: Measured 2 hours after eating
- •HbA1c: Average glucose over 2-3 months
Global Unit Standards
International Standard (mmol/L)
Used worldwide as the standard unit. Based on molar concentration, measuring the number of glucose molecules per liter of blood.
US Standard (mg/dL)
Commonly used in the United States. Based on mass concentration, measuring the weight of glucose per volume of blood.
Important: Always check which unit your lab or glucose meter uses to avoid confusion with your results.
Hypoglycemia Symptoms
- • Shakiness or trembling
- • Sweating
- • Rapid heartbeat
- • Dizziness or lightheadedness
- • Hunger
- • Confusion or irritability
- • Weakness or fatigue
Hyperglycemia Symptoms
- • Increased thirst
- • Frequent urination
- • Blurred vision
- • Headache
- • Fatigue
- • Slow-healing wounds
- • Fruity breath odor