This authentic Key Lime Pie recipe is easy and delicious! It has a buttery graham cracker crust and a sweet-tart creamy filling, bursting with fresh lime flavor.
💚 Traditional Key Lime Pie: This is the Real Deal
Key lime pie is the quintessential citrus dessert. It has a smooth and creamy lime filling that’s bracingly tart but not too sour – the perfect blend of sweet and tangy.
If you’re looking for the real deal, this key lime pie is it! It’s set atop a crisp, buttery graham cracker pie crust, and garnished with sweetened whipped cream. The refreshing tart taste makes it a perfect summer dessert, but you can enjoy it any time of year!
What’s in Key Lime Pie?
An authentic key lime pie filling has 3 main components:
- egg yolks
- sweetened condensed milk
- key lime juice
This may seem like an unusual combination, until you understand the origins of this classic American dessert.
Key lime pie originated in Key West, Florida in the late 1800s where key limes are plentiful. Since fresh milk and access to refrigeration weren’t readily available, people utilized canned milk, hence the sweetened condensed milk in this recipe.
(Wondering what the heck key limes are, and how they differ from “regular” limes? Check out our article about key limes vs regular limes here!)
More Summer Pie Recipes
Get your fill of fresh and fruity summer pies! Check out more of my must-make recipes like Grapefruit Meringue Pie, Strawberry Rhubarb Pie, Lime-Coconut Pie and Strawberry Lemonade Ice Cream Pie
Table of Contents
🧾 What You’ll Need
Ingredients & Substitutions
A few notes on the ingredients you’ll need for this pie. The full list of ingredients and the amounts needed can be found in the recipe card below. (Links are affiliate links and I earn a small commission from qualifying purchases.)
For the Crust
- Graham crackers: You’ll need about 10 rectangular graham crackers to make 6 oz (1 1/2 cups) of crumbs for the graham cracker crust. I love using a homemade graham cracker crust, but you can also use a pre-made graham cracker crust if you prefer.
- Unsalted butter and salt: I like to use unsalted butter when baking so that I can control the amount of salt. If you don’t have unsalted butter, just use salted butter and leave out the rest of the salt called for in the crust.
- Granulated sugar: Adds a touch of sweetness to the crust.
For the Filling and Topping
- Egg yolks: This recipe uses six large egg yolks. Here’s my full guide to separating egg yolks and whites if you need a refresher. Don’t forget to save the egg whites for a future batch of Meringue Cookies or buttercream!
- Sweetened condensed milk: Make sure to use sweetened condensed milk—not evaporated milk or another type of canned milk. The cans may look similar, but they are not the same thing and won’t give you the same results.
- Lime juice: Fresh key lime juice is traditionally used to make this pie, but you can use any limes that you have. You will need about 18-20 key limes ( or 5 large Persian limes) to get 1 cup of juice. To find the juiciest fruit, look for limes that are heavy for their size, and have a little give when you squeeze them. Check out our article on the difference between regular limes vs key limes if you want more information.
- Lime zest: Fresh lime zest adds an extra punch of lime flavor, as well as beautiful specks of green throughout the pie filling.
- Heavy whipping cream: To make the fluffiest, most stable whipped cream, use COLD heavy whipping cream. You can also chill your mixing bowl and beaters to speed up the whipping process.
- Powdered sugar: Helps to thicken and sweeten the topping.
Equipment
- Microplane: You can use a microplane to easily zest the limes. If you don’t have a one, a cheese grater will work as well.
- Juicer: Squeezing by hand works, but you don’t get nearly as much juice out of the limes. I recommend using a countertop juicer to maximize the juice you get out of your fruit.
- Pie pan: Use a 9 x 2″ pie plate for a deep-dish crust that can hold all the filling.
- Piping bag and Star tip: I like these disposable piping bags (I wash them and re-use them to reduce waste!) and used a large star tip (Ateco tip #867) to make the whipped cream rosettes.
Ready to Make These?
- Get the recipe below 👇👇
- Scroll below the recipe for step-by-step photos
- Read important Tips and FAQs
Leave a Review!
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Key Lime Pie
Ingredients
For the graham cracker crust:
- 10 graham crackers, to yield 6 oz / 1½ cups
- 3 oz unsalted butter, (6 TBSP), melted
- 1 ½ TBSP granulated sugar
- ¼ tsp salt
For the lime filling:
- 6 large egg yolks
- 2 cans sweetened condensed milk, (14 oz cans)
- 2 TBSP fresh lime zest
- 1 cup fresh lime juice, from about 18-20 key limes, or from about 9 medium or 5 large Persian limes
- ½ tsp salt
To finish:
- 1 cup heavy cream, cold
- ⅓ cup powdered sugar
- Lime zest and lime slices, to garnish
Instructions
To make the graham cracker crust:
- Crush the graham crackers in a food processor until they are fine crumbs. (Alternately, place them in a zip-top bag and roll over them with a rolling pin until very finely crushed.)
- Combine the graham cracker crumbs, about 2½ TBSP of the melted butter, granulated sugar, and salt in a bowl, and stir until well-combined. The mixture should have the texture of wet sand, and hold together a bit when you squeeze it between your fingers.
- If the crust still feels a bit dry, add the remaining butter and stir together to make it the proper texture.
- Press the crust evenly on the bottom and up the sides of a 9 x 2” pie plate. Bake at 350º F for 15 minutes, until set and lightly golden. Let the crust cool completely before filling.
To make the key lime filling:
- Preheat the oven to 350º F.
- Zest the fresh key limes with a microplane until you have 2 tablespoons of fresh zest, then juice the limes and measure out 1 cup of juice.
- Whisk together the yolks and 2 cans of sweetened condensed milk. Then add the lime zest, lime juice, and salt, and whisk until smooth and well-combined.
- Pour the filling on top of the baked and cooled graham cracker crust. Bake at 350º F for 20 minutes, until the center only slightly jiggles when you nudge the pie.
- Let the pie cool completely at room temperature, then refrigerate overnight.
To finish:
- Combine the heavy cream and powdered sugar in the bowl of a stand mixer fitted with a whisk attachment. Whip on medium-high speed until the cream is thick and holds medium peaks.
- Transfer to a piping bag with a star tip and pipe rosettes around the outer edge of the pie. Garnish with a sprinkle of lime zest on the whipped cream, and a twist of lime in the middle.
- Key lime pie will last for up to 5 days in the refrigerator.
Video
Recipe Notes
Baking Tips
- Use freshly squeezed juice
- Pre-bake the crust (prevents sogginess)
- Use a deep dish pie pan (2-inch deep)
- Chill the pie at least 6 hours to set
Make-Ahead Information
I don’t recommend making the filling far ahead of time, but you can prep the graham crust in advance. Assemble and bake the crust as directed, then store it in the fridge for 7 days or in the freezer for 3 months. When you’re ready to use it, thaw it in the fridge, then proceed with the recipe as instructed.Measuring Tips
Our recipes are developed using weight measurements, and we highly recommend using a kitchen scale for baking whenever possible. However, if you prefer to use cups, volume measurements are provided as well. PLEASE NOTE: the adage “8 oz = 1 cup” is NOT true when speaking about weight, so don’t be concerned if the measurements don’t fit this formula.
Want to learn more about baking measurements and conversion?
Nutrition
📷Photo Tutorial: How To Make Key Lime Pie
Here’s a quick overview of how to make the graham cracker crust and key lime pie filling for this easy Key Lime Pie recipe. Check the recipe card for printable instructions and ingredient measurements. And don’t miss the embedded video!
Make The sweet Graham Cracker Crust
- Make graham crumbs. Crush 10 graham crackers in a food processor until they are fine crumbs, or put them in a zip-top bag and roll over them with a rolling pin until crushed to make 6 oz (1 1/2 cups) graham cracker crumbs.
- Mix crumbs, melted butter, sugar and salt. Combine graham cracker crumbs, 3 oz (6 TBSP) melted butter,1 1/2 TBSP granulated sugar, and 1/4 tsp salt in a medium bowl.
- Stir. Stir everything together until it’s well-combined and has the texture of wet sand.
- Press into pan. Press the crust mixture evenly on the bottom and up the sides of your pie pan.
- Bake and cool crust. Bake at 350ºF for 15 minutes. Allow it to cool completely on a wire rack before adding the filling.
Make The Key Lime Pie Filling
- Zest limes. Zest the fresh key limes with a microplane until you have 2 TBSP of fresh zest.
- Juice limes. Juice the limes and measure out 1 cup of juice.
- Mix egg yolks and milk. In a large mixing bowl, whisk together 6 large egg yolks and 2 cans (28 oz total) of sweetened condensed milk.
- Add lime juice and zest. Add 1 cup fresh lime juice, 2 TBSP zest and 1/4 tsp salt to the bowl.
- Whisk the filling. Stir until it’s thick and smooth.
- Fill crust and bake. Pour the filling into the baked and cooled graham cracker crust, and bake at 350ºF for 20 minutes. The pie is done when the center barely jiggles when you move the pan.
- Cool completely. Let the pie cool at room temperature, then refrigerate for at least 6 hours so it sets up completely.
Decorate The Pie
- Make whipped cream. Combine 1 cup heavy whipping cream and 1/3 cup powdered sugar in the bowl of a stand mixer fitted with a whisk attachment. Whip on medium-high speed until the cream is thick and holds medium-stiff peaks.
- Pipe whipped cream. Transfer the mixture to a piping bag with a star tip and pipe rosettes around the outer edge of the pie.
- Garnish. Finish with a sprinkling of lime zest and a twist of lime in the center.
- Slice, serve, and devour!
💭 Variations
Wanting to switch things up? Here are a couple suggestions:
- Use store-bought crust. If you want to save a little bit of time, you can use a store-bought graham cracker crust. However, store-bought crusts might be shallower than homemade crust, so you may end up with a little extra key lime filling.
- Try a different crust flavor. Instead of graham crackers, try using shortbread cookies, gingersnaps, or crunchy coconut cookie crumbs.
- Go for meringue. Try toasted meringue instead of whipped cream for the topping.
- Switch up the citrus. Most sour citrus fruit will work in this recipe, and produce a delicious creamy sweet-tart filling. Lemon is a natural choice, but grapefruit is delicious too! If you want to make this with orange, I suggest using half orange and half lemon juice, since oranges are much sweeter and the pie needs some of lemon’s sourness to balance it out.
💡 Tips and FAQs
Here are a few of my tips to make the best Key Lime Pie!
- Use freshly squeezed juice. Bottled juice contains preservatives that can make the juice taste “off” or slightly stale. I recommend freshly squeezing the lime juice for the best flavor!
- Pre-bake the crust. While graham cracker crusts can sometimes be used without baking, this pie is best with a pre-baked crust. The extra baking time ensures the graham crust doesn’t get soggy.
- Let the crust cool. After you pre-bake the crust, let it cool completely before you add the filling so it has time to firm up.
- Use a 2-inch deep pie pan. This recipe makes enough filling to fill a deep dish crust, so I recommend using a 2-inch deep pan.
- Chill the pie. After the pie is prepped and baked, chill it in the fridge overnight (or for at least 6 hours) before you cut into it so it can set.
“Regular” limes, or Persian limes, are the limes we typically see in grocery stores. They’re larger, with a thicker peel and dark green skin.
Key limes, also known as Mexican limes or West Indian limes, are small, round limes with a yellow-green color, thin skin, and a bright, intense lime flavor.
For lots more information about key limes, don’t miss our detailed post about the difference between regular limes and key limes!
Absolutely! Regular limes will still produce a delicious pie. You don’t need to make any adjustments — just use the same amount of zest and juice called for in the recipe.
It’s true that you can buy bottled key lime juice, but I don’t recommend using it. Bottled juice just doesn’t taste the same as fresh juice. It has a harsh, flat, one-dimensional taste that’s far inferior to fresh juice. Whenever possible, I recommend using fresh limes of any type instead of bottled lime juice.
Key lime pie will last for up to 5 days in the refrigerator.
I don’t recommend making the filling far ahead of time, but you can prep the graham crust in advance. You can assemble and bake the crust as directed, then store it in the fridge for 7 days or in the freezer for 3 months. When you’re ready to use it, thaw it in the fridge, then proceed with the recipe as instructed.
WOW!!!! What a great idea and so simple too. I know I can make this one with no problem. I have my own lemon and lime tree in my yard so I have the fruit. I always have graham crackers on hand for a snack so I’m good to go. My son loves this pie so I can’t wait to make it for him. I might even turn it into a cheesecake on the bottom and the pie part on top. Thank you for the recipe. I love it already.
Hi Donna. I’m so jealous of your trees! I love citrus. I’m so glad you found my recipe. I really hope you enjoy it and I LOVE the idea of cheesecake on the bottom. Yum!
This looks very good. How would I adjust the cooking times if I made individual pies?
Hi Janet! We’ve never tested this recipe for making it into mini pies, so I can’t give you any specifics of how to do it. I can tell you to follow the basic instructions and watch the baking process like a hawk. For example, when you make the crust and press into your mini pans, you can still bake them at 350 but they will likely turn golden before 15 minutes. Remove them from the oven by the way they look and not the time. Same with baking the filling. Bake them at the same temperature but watch for signs that the pies have firmed around the edges and slightly jiggle in the center. It’s harder to tell if the center jiggles on mini pies, but you just don’t want to overcoook them. You might take notes on what you try doing so that you’ve got a better idea if you try it a second time. I hope that helps. Best of luck.