By and large, if your foreskin covers all or almost all of your glans while flaccid, you're probably uncut. The best way is probably checking for the ridged band, which is an area of erogenous tissue around the frenulum on the underside of the penis, which is removed during any circumcision. It's hard to explain what that looks like, though.
Look at the image on the first post, and you can read the post, too. That should make it pretty clear.
If you're circumcised, you will have your glans (head) showing. If you're not, you'll have some skin over the head that you should be able to pull back and that should retract upon getting an erection.
WWJD - What WOULD Jesus do? Read Matthew, chapters 5-7 in the Bible - and find out now!
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