This quick and easy key lime pie recipe starts with a graham cracker crust and is filled with a mixture of egg yolks, sweetened condensed milk, key lime juice & zest. Topped with fresh whipped cream and a lime twist garnish, it’s a refreshing pie that tastes like the tropics and is a must-make this summer!

Slices of key lime pie on plates with dollops of whipped cream and lime slices.

Looking for more key lime recipes? Try my No-Bake Key Lime Cheesecake and Key Lime Pie Bars.


Over ten years ago, I was on vacation in Florida, having lunch at a fabulous restaurant called the Old Key Lime House, when I faced the all-important decision of what to order for dessert. 

There was a triple-layer chocolate cake which would normally be my go-to. But there was also homemade key lime pie, and since the restaurant bore the iconic dessert’s name, I HAD to order it! 

One bite in, and I was completely smitten with the flavor and cool, creamy texture. I vowed then and there to eat (and make!) more key lime pie. 

The History of Key Lime Pie

Key lime pie dates back to the late 1800s in the Florida Keys. Modern refrigeration wasn’t available at the time, so fresh milk wasn’t a common commodity. Instead, canned milk was widely used. As a result, this incredibly easy pie came to be.

Believe it or not, up until recently, this was a purely no-bake pie. Combining the lime juice with the egg yolks and condensed milk creates a chemical reaction that causes the mixture to thicken all on its own (the acid causes the proteins in the yolks and milk to bond together).

Nowadays, the pie is baked due to concerns over raw eggs, creating a much better filling consistency since it sets wonderfully and is less droopy than its unbaked counterpart.

Key lime pies can be made with a graham cracker crust (featured here) or pastry pie crustmeringue topping (more traditional), or a whipped cream topping (more modern). 

Overhead photo of baked key lime pie adorned with dollops of whipped cream and lime slices.

Ingredients Overview

Only four ingredients each are needed for the graham cracker pie crust and the classic key lime pie recipe; a very simple pie indeed! 

  • Graham Cracker Crumbs: You can crush whole graham crackers or buy the boxed graham cracker crumbs.
  • Light Brown Sugar: To sweeten the crust.
  • Melted Butter: To hold the pie crust together.
  • Salt: Balances the flavors of the graham cracker crust.
  • Sweetened Condensed Milk: You need one 14-ounce can; this will thicken and sweeten the filling.
  • Key Lime Juice: Fresh juice from key limes is preferred, but if you can’t get fresh key limes, then you can use bottled juice; Nellie & Joe’s Key Lime Juice is the best! You can find it at most grocery stores.
  • Key Lime Zest: If you cannot find key limes, you can use regular lime zest.
  • Egg Yolks: The yolks thicken and add richness to this pie. Use the leftover egg whites for a meringue topping or meringue cookies!
Ingredients for key lime pie filling prepped and labeled.

Key Limes vs. Regular Limes

If you’ve never seen key limes, you might wonder what the difference is between the two. 

Key limes are significantly smaller than regular (Persian) limes and are more acidic, resulting in a tarter flavor. Their flesh and juice are also yellow in color, unlike the traditional green color of regular limes.

How to Make Key Lime Pie

After eating it for the first time, I was convinced that authentic key lime pie filling was an elaborate curd/custard that would need to be painstakingly cooked on the stove and then baked in the oven. Not so!

  1. Prepare the Filling: Whisk together the lime zest, egg yolks, sweetened condensed milk, and lime juice, then set it aside to thicken.
  2. Make the Graham Cracker Crust: Stir together my favorite graham cracker crust, press it into a 9-inch pie pan, and bake it briefly, then let it cool to room temperature.
  3. Bake the Pie: Once the crust cools, pour the thickened filling into it and bake until it is mostly set but still jiggles a bit.
  4. Chill Out! After the pie cools to room temperature, it must be refrigerated for at least a few hours. This pie tastes the best chilled, and it helps the filling to finish setting up properly.
Collage of photos showing graham cracker crust, key lime pie filling, and the filling inside the crust.

Recipe Notes

  • Pan: A 9-inch pie plate is used for this recipe.
  • Key Lime Juice: If you cannot get fresh key limes, use bottled key lime juice for this pie. The recommended brand is Nellie & Joe’s (available at most grocery stores). While the flavor will be significantly different, you can also use regular limes or a combination of lime and lemon juice.
  • Key Lime Zest: If you cannot get fresh key limes, you can substitute regular lime zest.
  • Make-Ahea​​​​d: This pie can be made up to 2 days in advance. Wait to top with whipped cream until the day you serve it.
  • How to Store the Pie: Refrigerate the pie, loosely covered with plastic wrap, for up to 3 days.
  • Freezing Instructions: Place the entire pie, uncovered, in the freezer until completely frozen. Then wrap well in plastic wrap and then a layer of foil (or place in a freezer-safe Ziploc bag) and store in the freezer for up to 1 month. Thaw in the refrigerator overnight.
Slice of key lime pie on a plate with a fork, topped with small swirl of whipped cream and lime slice.

Watch the Recipe Video:

More Delicious Summer Pies

If you make this key lime pie and love it, remember to stop back and give it a 5-star rating – it helps others find the recipe! ❤️️

Traditional Key Lime Pie Recipe

Quick and easy key lime pie recipe starts with a graham cracker crust and filling of egg yolks, sweetened condensed milk, key lime juice & zest.
4.90 (231 ratings)

Ingredients

For the Lime Filling:

  • 4 teaspoons grated key lime zest
  • 4 egg yolks
  • 14 ounces sweetened condensed milk
  • ½ cup (114 g) fresh key lime juice

For the Graham Cracker Crust:

  • 2 cups (200 g) graham cracker crumbs, (approximately 14 full graham crackers)
  • cup (71 g) light brown sugar
  • ½ cup (113 g) unsalted butter, melted
  • Pinch salt

For the Whipped Cream Topping:

  • cups (360 ml) heavy cream, chilled
  • ½ cup (57 g) powdered sugar
  • ½ teaspoon vanilla extract

Instructions 

  • Preheat oven to 350 degrees F.
  • Make the Filling: Whisk the lime zest and egg yolks in a medium bowl for 2 minutes. Whisk in the sweetened condensed milk, then the lime juice. Set aside at room temperature to thicken while you prepare the crust.
  • Make the Crust: In a medium bowl, stir together the graham cracker crumbs, brown sugar, and salt, ensuring no lumps of brown sugar remain. Drizzle the melted butter over the graham cracker mixture and toss to combine with a fork, ensuring the mixture is evenly moistened. Press the crust mixture evenly into the bottom and sides of a 9-inch pie plate, and pack tightly using the back of a measuring cup. Bake for 10 minutes; transfer to a wire rack to cool to room temperature.
  • Once the crust has cooled to room temperature, pour the lime filling into the crust. Bake until the center is set yet still wiggly when jiggled, 15 to 17 minutes. Return the pie to a wire rack; cool to room temperature. Refrigerate until well-chilled, at least 3 hours, or overnight.
  • Make the Whipped Cream: Using an electric mixer, whip the cream on medium speed until soft peaks form. At this point, add the powdered sugar, a small amount at a time, then the vanilla extract, while continuing to whip the cream until stiff peaks form. Decoratively pipe the whipped cream over the filling or spread the whipped cream evenly with a spatula. Garnish with lime slices, if desired, and serve. Cover leftovers with plastic wrap and refrigerate for up to 3 days.

Notes

  • Pan: A 9-inch pie plate is used for this recipe.
  • Key Lime Juice: If you cannot get fresh key limes, use bottled key lime juice for this pie. The recommended brand is Nellie & Joe’s (available at most grocery stores). While the flavor will be significantly different, you can also use regular limes or a combination of lime and lemon juice.
  • Key Lime Zest: If you cannot get fresh key limes, you can substitute regular lime zest.
  • Make-Ahea​​​​d: This pie can be made up to 2 days in advance. Wait to top with whipped cream until the day you serve it.
  • How to Store the Pie: Refrigerate the pie, loosely covered with plastic wrap, for up to 3 days.
  • Freezing Instructions: Place the entire pie, uncovered, in the freezer until completely frozen. Then wrap well in plastic wrap and then a layer of foil (or place in a freezer-safe Ziploc bag) and store in the freezer for up to 1 month. Thaw in the refrigerator overnight.
Calories: 516kcal, Carbohydrates: 52g, Protein: 7g, Fat: 31g, Saturated Fat: 18g, Cholesterol: 194mg, Sodium: 189mg, Potassium: 272mg, Sugar: 41g, Vitamin A: 1145IU, Vitamin C: 6.4mg, Calcium: 198mg, Iron: 1mg

Did you make this recipe?

Leave a review below, then snap a picture and tag @thebrowneyedbaker on Instagram so I can see it!

Update Notes: This recipe was originally published in May 2012.

[photos by Ari of Well Seasoned]