Oregano vs. Parsley: A Hearty Dried Herb and a Delicate Fresh One

Oregano flavors a dish; parsley freshens it. Oregano is a mint-family herb built on the phenols carvacrol and thymol, and it stands up to drying and long cooking. Parsley is a carrot-family herb with a mild, slightly bitter flavor and very little essential oil, and it’s best fresh and added late. People often suggest one as a stand-in for the other, but only one direction comes close, and only for color or a green note, not flavor.

Side by side

Greek and Italian culinary oreganos have a strong aroma and a warm, pungent taste, and parsley is mildly aromatic. PROSEA describes parsley oil’s flavor as warm but slightly burning and bitter.²

The chemistry, sample by sample

These are essential-oil figures from particular samples, collected in two reference works. They come from different studies, so don’t merge them.

The two herbs share no lead compound, and parsley has far less oil to begin with. That fits how they behave in the pot: oregano carries a dish, parsley brightens it.

The differences that change a dish

Dried or fresh

America’s Test Kitchen’s Danielle Lapierre puts oregano among the herbs that dry well, and parsley on her list of herbs better fresh, which she says lose a lot of flavor once dried.⁶ In ATK’s dried-versus-fresh tests, dried oregano held up reasonably well in dishes with more than 20 minutes of cooking and plenty of liquid.⁷

You’ll hear that oregano gets used dried because fresh oregano is too strong, and drying makes it milder. The University of Delaware’s extension guide gives the general rule the other way around: dried herbs are stronger than fresh.⁸ Oregano dries well because its flavor survives the process, not because drying tames it.

When it goes in

LSU AgCenter groups parsley with the delicate herbs you add a minute or two before cooking ends, and oregano with the sturdier ones.⁹ In a tomato sauce, oregano can go in early and parsley at the end.

Flat-leaf and curly parsley

PROSEA says flat-leaved parsley has a stronger flavor than the curly type, and that curly leaves usually go toward garnishing and seasoning.² America’s Test Kitchen recommends flat-leaf when parsley is a major player, as in its tabbouleh and salsa verde.¹⁰ See Italian parsley vs. curly parsley.

Where each one belongs

Oregano is essential in Italian pizza and pasta sauces, Greek salads and gyros. Britannica says it only caught on in the United States after World War II, when returning soldiers who’d picked up a taste for Italian food made it popular.¹¹ Parsley is one of the fines herbes, with chives, tarragon and chervil. It’s also the base of chimichurri, persillade and gremolata, though we didn’t find a source we could open that documents those recipes.

Can one stand in for the other?

Only up to a point, and neither one copies the other’s flavor.

• Oregano in place of parsley. Healthline says to use less oregano than parsley, because oregano’s flavor is much stronger.¹² Start with about a quarter of the parsley amount and taste, and keep oregano out of dishes where parsley is the main ingredient, like tabbouleh or a parsley sauce. Our parsley substitutes page uses the same starting point.
• Parsley in place of oregano. The Spice House suggests parsley among the swaps for Greek or Mediterranean oregano,¹³ and A Couple Cooks says a small handful of flat-leaf parsley could work in a pinch.¹⁴ Neither gives an amount. Parsley adds a green note, not oregano’s warmth. Use it fresh, near the end, starting with the same amount as the oregano. See oregano substitutes for closer matches like marjoram.
• Color only. Dried parsley flakes look a lot like dried oregano in a soup or meatball mix, and add little flavor.

What isn’t known

• We found no source for the claim that oregano and parsley are among the most popular herbs in American cooking, or that pizza sauce is known for an especially strong oregano flavor.
• Persillade, chimichurri and parsley with hummus get described all the time, but we couldn’t open a source documenting them.

Related

• Profiles: oregano, parsley, marjoram, chervil
• Substitutes: oregano substitutes, parsley substitutes
• Comparisons: basil vs. parsley, cilantro vs. parsley, chervil vs. parsley, oregano vs. thyme, basil vs. oregano, cilantro vs. oregano
• Fresh and dried: fresh oregano vs. dried, fresh parsley vs. dried
• Too much oregano? and too much parsley?