Depends what I eat, what my BG was when I ate and how long before eating I pre-bolused.
I try to keep my levels below 10mmol/l but am not concerned if they spike above this and fall back down quickly.
I am also aware that CGMs will exaggerate spikes in double figures. If my CGM say 12mmol/l, for example, I usually double ch3vknwith a finger prick and find it is not so high.
Why do you ask?
Are you experiencing spikes that concern you?
if so, how high and how long is the spike?
If your levels return to normal it is likely that you bolus dose is correct but you are not pre-bolusing early enough (your carbs are digested before your insulin starts working) . If your levels stay too high, it is likely your dose is too low.