A hardy Mediterranean herb with small leaves and a pungent, peppery, slightly bitter aroma driven by carvacrol.
What it does in a recipe: An assertive savoury herb that anchors Greek, Italian and Mexican cooking and holds its own through simmering. Pick the swap that covers that job — the ratios below are written so you can act on them without doing any arithmetic.
Thymol and carvacrol are structurally near-identical phenols, which is why thyme and oregano can stand in for each other. Thyme is milder, so increase the amount.
Trade-offMore floral and less peppery. In a Greek dish the loss of oregano's bitterness is obvious.
Mexican oregano is a different plant from Mediterranean oregano, with a more citrusy, less peppery flavour. They are not interchangeable in either direction without a noticeable shift.
Cooking around an allergy? Diet tags here describe the ingredient itself, not any particular brand. Processed products change formulation without notice and shared production lines are common, so read the label on everything you use. A severe allergy is a medical matter — confirm with the manufacturer or your clinician rather than relying on a substitution chart.