It’s a juicy topic.

Lime Slices

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If you’ve ever asked yourself (or the internet) “What is the difference between regular limes and Key limes?” it’s as likely to have been in frustration as in mere curiosity.

We’ve all been there before: You’re in the grocery store with your shopping list, ticking off ingredients as they go into the cart when you realize that the next item you need isn’t there. They don’t carry it, or they’ve run out of stock.

The other store is like, a 20-minute drive away… surely this similarish-sounding ingredient will work? Especially, you figure, if the two look and smell more or less alike; perhaps they even belong to the same family. What difference will it really make?

Well, in the case of “regular” limes vs. Key limes, the truth is, not a ton. Of course there’s more separating the two than meets the eye, but the differences are fairly minute and, indeed, the two can often be used interchangeably in recipes without risk of total disaster.

Though, naturally, it stands to reason that Key lime pie is not Key lime pie without the use of its namesake citrus. So, let’s break it down.

What’s in a name?

First things first: What we, here in the States, think of as “regular” or “conventional” limes, are actually technically called Persian limes or Tahitian limes (Citrus latifolia). They’re actually much less common worldwide than the Key lime, which is also known as the Mexican lime or West Indian lime (Citrus aurantifolia).

The latter’s Florida connection dates back to the turn of the last century, where they were commercially produced until a hurricane in the late 1920s pretty much wiped the crop out. Following that, production largely switched over to the more efficient and disease-resistant Persian variety.

While many residents in the Key region still grow the eponymous trees on their property, most of the Key limes you find in stores here are sourced from Mexico.

How are Key limes different from regular limes?

Smaller though they may be, Key limes are actually known for having a bolder, slightly herbal-floral aroma and packing much more of an acidic punch than their Persian brethren.

Aesthetically, Key limes tend to have a more yellow-ish tint to their green, the feel of the rind is a little more leathery, and inside, you’ll find significantly more seeds. Which brings up the subject of work: There’s no denying that Key limes require a lot more of it — especially when you consider yield (not a lot) versus the cost (sometimes up to two or three times more than a Persian lime).

What other types of limes are there?

Another type of lime that turns up a lot in Southeast Asian recipes are makrut lime (Citrus hystrix). They are easy to spot by their bumpy, wrinkled skin. Makrut lime leaves may be easier to find than the fruit itself, especially in Asian grocery stores. They lend a floral, citrusy fragrance to Thai dishes that’s like a combo of Persian lime, lemon, and orange essence. The actual fruit isn’t very juicy, but the zest can be used like the leaves, to infuse flavor into soups, sauces, and curries.


You might also see calamansi (Citrus mitis) in an ingredient list for a Filipino dish, and it sometimes goes by the name Philippine lime or golden lime — but it’s not actually a lime at all. (Besides which, these small, thin-skinned citrus fruits don’t travel well, so they can be hard to find, but if you do get your hands on some, expect a taste somewhat like a sour orange.)