Read the label. If it says “vanillin” anywhere, it’s imitation. If it lists “vanilla bean extractives,” it’s real gold.
Price is a giveaway. A tiny bottle of real extract costs more than a bottle of wine. That’s a good thing. It means you’re buying quality.
Smell the cap. Real extract smells like a bakery. Imitation smells like a scented candle. Trust your nose, it never lies.