Diabetes Home Testing


Why do I have to test my blood sugar?

Testing your blood sugar is the best way to find out how well your diabetes is managed. A log book of your blood sugar levels will help you see how food, physical activity, and diabetes medicines affect your blood sugar. If your blood sugar is too low or too high, your health care provider might want to adjust your diet, exercise, or the amount of medicine you are taking. Take your log book with you whenever you visit your health care provider.

When should I test my blood sugar?

The most common times to test your blood sugar level are before meals and at bedtime. Your health care provider will tell you how often and when to check your blood sugar.

What tests do I need to do at home?

  • Blood test: The blood test is used to measure the amount of sugar in your blood. It’ll help you find out if your meal plan, exercise and medicine are working to regulate your blood sugar.
  • Urine test: The urine test looks for ketones in your urine. This can be done if you are sick or if your blood sugar level is very high. Meters are also available that can test your blood for ketones.

Test Details

How do I test my blood sugar?

The usual blood sugar test involves pricking your finger with a small needle called a lancet, putting a drop of blood on a test strip, and using a meter that displays your blood sugar level. Blood sugar meters and test strips are available at your local pharmacy, through mail order, or through your health care provider. There are many different types of meters. Your health care provider can help you select the meter that is best for you. Some insurance companies might cover the cost of these supplies. Call your insurance company if you have any questions.

What should my blood sugar level be?

The paragraph below gives you an idea of what your blood sugar levels should be. Blood sugar ranges might be different for each person and can change throughout the day. Your health care provider will tell you what range is good for you. Call your health care provider if one of the following applies:

  • Your blood sugar test results are higher than usual (more than 100 mg/dl above your usual results) for more than two days for an unknown reason.
  • Your blood sugar level is low (less than 70 mg/dl) more than 2 times a week.

Time of test goal

  • Before meals: 80-130 mg/dl
  • Two hours after meal starts: <180 mg/dl
  • Before bedtime snack: 100-150 mg/dl

Source: American Diabetes Association, 2009

What should I know about ketones?

Ketones appear in your urine when your body uses its own fat for energy instead of sugar. Ketones usually appear when your blood sugar level is more than 300 mg/dl. If ketones build up in your blood, you can develop a very dangerous health condition known as ketoacidosis. Ketones are most likely to occur in people with Type 1 diabetes.

How do I test for ketones?

The most common way to test for ketones is by dipping a test strip into your urine. The test strip changes color, which is then matched to a chart that shows the level of ketones in your urine. There are also meters available that can test your blood for ketones.

When should I test for ketones?

Test for ketones if your blood sugar level is 300 mg/dl or higher or if you feel ill.

Last reviewed by a Cleveland Clinic medical professional on 02/28/2017.


  • American Diabetes Association. Blood Glucose Testing (http://www.diabetes.org/living-with-diabetes/treatment-and-care/blood-glucose-control/?loc=DropDownLWD-bloodglucose) Accessed 11/9/2021.
  • American Heart Association. Symptoms, Diagnosis and Monitoring of Diabetes (http://www.heart.org/HEARTORG/Conditions/More/Diabetes/SymptomsDiagnosisMonitoringofDiabetes/Symptoms-Diagnosis-Monitoring-of-Diabetes_UCM_002035_Article.jsp#.WL65TP6V5RA) Accessed 11/9/2021.
  • U.S. Food and Drug Administration. Blood Glucose Monitoring Devices (http://www.fda.gov/medicaldevices/productsandmedicalprocedures/invitrodiagnostics/glucosetestingdevices/default.htm) Accessed 11/9/2021.

Cleveland Clinic is a non-profit academic medical center. Advertising on our site helps support our mission. We do not endorse non-Cleveland Clinic products or services. Policy