Honestly? The best way to tell is to call your friend who works at the shop. Or—here’s a crazy idea—just ask for the bag. The label never lies (legally). Everything else is just guesswork and giggles.
But if you’re out on a blind date and don’t want to be rude? Sip slowly. If your date starts talking faster and about mortgages? That’s regular. If they yawn and ask about your cat’s sleep schedule? That’s definitely decaf.
So, my friend, you now have the tools. Use them wisely. And if you still can’t tell? Just drink both. That’s the magic of coffee: it’s all delicious, even when you’re confused. Now go get caffeinated—or decaffeinated—and live your best life.