A continuous glucose monitor uses a tiny sensor inserted just under the skin to measure glucose in interstitial fluid every few minutes. It shows your current level, the direction it is heading, and trends over hours and days, which finger-pricks alone cannot capture.
This is especially useful for spotting overnight lows, understanding how meals and exercise affect you, and reducing the number of finger-pricks. Some systems alarm when levels go too high or low. Because interstitial readings lag slightly behind blood, some devices still need occasional finger-prick checks, particularly when levels are changing fast or before treating a hypo.
Availability, funding, and suitability differ by country and by diabetes type. Ask your care team whether a CGM is appropriate and available for you, and how to interpret the time-in-range data it produces.