Pie Crust Recipe Calculator

A standard 9-inch single-crust pie shell uses 1.25 cups of all-purpose flour, and the classic ratio by weight is roughly 3 parts flour to 2 parts fat to 1 part water — though in practice the fat is a bit more generous than that strict ratio suggests.

The exact recipe scales by the pie dish area, since you need more dough to cover a larger circle.

scale_factor = (desired_diameter / 9)²

A 10-inch pie has an area 24% larger than a 9-inch pie, not 11% larger as people assume from the diameter difference.
This is why store-bought 9-inch crusts always seem too small for the 10-inch dish hiding in the back of the cupboard.

Base amounts for a 9-inch single crust:

• All-purpose flour: 156 g (1.25 cups)
• Cold butter (or shortening): 113 g (1/2 cup, 8 tbsp)
• Ice water: 45-60 ml (3-4 tbsp)
• Salt: 1/2 tsp

For an all-butter crust, the fat percentage is about 72% of flour weight.
For a shortening crust, the fat is typically 64% of flour weight — shortening is 100% fat while butter is about 80%, so you need less shortening by weight.

Butter produces better flavor and a flakier, less greasy crumb.
Shortening produces a more tender crumb that is easier to roll.
A 50/50 blend gets you both.

The cold water is variable — humidity and flour absorption vary significantly.
Always add water one tablespoon at a time until the dough just barely holds together when squeezed.
Too little water and the crust crumbles; too much and it becomes tough.

Resting in the refrigerator for at least 30 minutes after mixing is not optional — it lets the gluten relax and makes rolling out dramatically easier.