Key Lime Cake Recipe

Name: Key Lime Cake Recipe
Prep time: 35 min
Cook time: 25 min
Total time: 60 min
Ingredients: 1 box lemon cake mix; 1 box lime Jell-O (3 oz); 1/3 cup vegetable oil; 3 eggs; 1/2 cup orange juice (Minute Maid Orange Juice Coupon); 3/4 cup water; 4 Tbsp confectioners sugar; 1/4 cup lime juice (bottled); 1/4 cup lime juice (fresh, about 2 limes); 1.5-2 cups confectioners sugar; 8 oz cream cheese (softened); 1 stick margarine or butter (softened); 1 tsp vanilla

4.34 / 5 ( 3 Reviews )

9 Comments Jump to Recipe

Cathy Yoder Updated on May 12, 2026 The links in the post below may be affiliate links. Read the full disclosure

Box Mix Key Lime Cake Recipe with Cream Cheese Frosting

slice of box mix key lime cake with cream cheese frosting

Easy Key Lime Cake from a Cake Mix

If you love key lime pie but want an easy dessert that feeds a crowd, this box mix key lime cake is a fun shortcut recipe with big citrus flavor. It starts with a lemon cake mix, gets a boost from lime gelatin, and finishes with a creamy homemade cream cheese frosting that makes the whole cake taste bright, sweet, and a little tangy.

This is not a fussy from-scratch layer cake, and that is exactly why it works. The cake mix keeps the layers soft and reliable, the lime gelatin adds color and flavor, and the frosting balances the sweetness with just enough cream cheese richness. It is a great spring or summer dessert, but it is also cute for birthdays, potlucks, Easter, St. Patrick’s Day, or anytime you want a green cake that actually tastes good.

One note before you bake: true key limes can be harder to find depending on where you live. Regular limes still work in this cake, but bottled key lime juice is an easy way to get that classic key lime flavor without squeezing a million tiny limes. If you are curious about the fruit itself, the University of Florida notes that key limes are also known as West Indian or Mexican limes, and they are smaller and more tart than the Tahitian limes most commonly found in grocery stores. Learn more about key limes from UF/IFAS.

Why You’ll Love This Key Lime Cake

This cake has the nostalgic feel of an easy boxed cake mix dessert, but the flavor is more special than a plain cake from the box. It is sweet, limey, soft, and creamy, with enough citrus flavor to make it feel refreshing instead of heavy.

Starts with a cake mix: This keeps the recipe easy and dependable.
Bright lime flavor: Lime gelatin and lime juice give the cake its fun citrus flavor.
Great for gatherings: A three-layer cake looks impressive without requiring complicated steps.
Cream cheese frosting: The tangy frosting helps balance the sweet lime cake.
Make-ahead friendly: The frosted cake stores well in the refrigerator.

Reader Tara said, “Yum! I love everything and anything Key Lime! Can’t wait to try it!” And if you are thinking about turning this into cupcakes, you are not alone — Melanie had the same idea in the comments. This batter should work well for cupcakes, but you will want to reduce the bake time and start checking early.

Key Lime Cake Ingredients

ingredients for box mix key lime cake including cake mix and lime gelatin

The beauty of this recipe is that it uses simple ingredients and turns them into a dessert that feels homemade. You will need a lemon cake mix, lime gelatin, oil, orange juice, eggs, lime juice, cream cheese, butter, and powdered sugar.

The lemon cake mix adds a citrus base, while the lime gelatin brings in the classic green color and extra lime flavor. The orange juice may sound surprising, but it helps make the cake moist and adds another layer of citrus flavor without overpowering the lime.

How to Make Key Lime Cake with Cake Mix

Start by preparing your cake pans well so the layers release cleanly. Grease the pans and use wax paper or parchment paper in the bottom if that is how your recipe card directs it. Since this is a layer cake, a little prep at the beginning saves a lot of frustration later.

Mix the cake batter according to the recipe card, combining the cake mix, lime gelatin, oil, orange juice, and eggs until smooth. Divide the batter evenly between the pans and bake until the cakes are set and a toothpick inserted in the center comes out clean.

Let the cake layers cool before frosting. This part matters because cream cheese frosting can soften quickly if the cake is still warm. Once cooled, remove the first cake from its pan, discard the wax paper, and spread a layer of icing on top. Remove and stack the second cake layer on top of the first and spread another layer of icing. Add the third layer, frost the top, then use the remaining icing to cover the sides.

Store the cake in the refrigerator so the frosting stays firm and the layers slice more cleanly.

Helpful Tips for the Best Box Mix Key Lime Cake

Use bottled key lime juice if needed. Fresh key limes are great, but bottled key lime juice is convenient and consistent.
Regular limes are okay. The flavor will be a little different, but the cake will still be delicious.
Do not frost a warm cake. Let the layers cool completely before adding cream cheese frosting.
Chill before slicing. Refrigerating the cake helps the frosting firm up and makes cleaner slices.
Skip extra food coloring if you want. Lime gelatin already gives the cake a green tint.

If you want a stronger lime flavor, add a little fresh lime zest to the frosting. Lime zest gives you fragrance and flavor without watering down the frosting. Just be careful not to add too much extra lime juice to cream cheese frosting, or it can become thinner than you want for a layer cake.

How to Serve Key Lime Cake

This cake is sweet and citrusy, so it pairs well with simple sides. Serve it with fresh strawberries, raspberries, or a scoop of plain vanilla ice cream. For a cleaner presentation, chill the cake first, then use a sharp knife wiped clean between slices.

Because this cake has cream cheese frosting, keep leftovers covered in the refrigerator. It is a nice make-ahead dessert because the lime flavor has time to settle into the cake, and the frosting firms up beautifully once chilled.

More Easy Dessert Recipes

If you love simple desserts that still feel special, try these reader-friendly favorites next:

Key Lime Cake FAQ

Can I make key lime cake with a boxed cake mix?

Yes. This recipe starts with a boxed lemon cake mix and adds lime gelatin, orange juice, and homemade cream cheese frosting to make it taste more special than a plain box cake.

Do I have to use real key limes?

No. Real key limes are wonderful when you can find them, but bottled key lime juice or regular lime juice can also work. The flavor will vary slightly, but the cake will still have a bright lime taste.

Why does this recipe use lime gelatin?

Lime gelatin adds lime flavor, moisture, sweetness, and the fun green color that makes this cake stand out.

Can I make this key lime cake into cupcakes?

Yes, this batter should work for cupcakes. Fill the cupcake liners about two-thirds full and start checking for doneness much earlier than the full cake layers.

Does key lime cake need to be refrigerated?

Yes. Because this cake uses cream cheese frosting, store it covered in the refrigerator. Chilling also helps the frosting firm up and makes the cake easier to slice.

Can I make this cake ahead of time?

Yes. You can make the cake a day ahead and store it in the refrigerator. The lime flavor may even taste better after the cake has chilled.

Printable Box Mix Key Lime Cake Recipe

This easy key lime cake is sweet, citrusy, creamy, and made simple with a boxed cake mix. It is a fun dessert for spring, summer, holidays, birthdays, and potlucks.