A blood glucose test measures the amount of sugar, or glucose, in your blood. This test is important for diagnosing and managing conditions like diabetes. It can be done using a small device called a glucometer, which provides quick results, or through a laboratory test that may require a blood sample drawn from a vein. There are different types of blood glucose tests, including fasting blood glucose tests and oral glucose tolerance tests. Fasting tests require you to avoid food for a certain period before the test, while oral tests involve drinking a sugary solution before measuring your blood sugar levels at intervals.