Candy Temperature Calculator
Candy making is one of the most temperature-sensitive forms of cooking. The exact temperature you cook sugar syrup to determines whether your candy becomes fudge, caramel, toffee, or brittle. Each distinct stage corresponds to a different sugar concentration and different physical properties of the cooled candy. To complicate matters, the standard temperature ranges are calibrated for sea level. If you live at high altitude, water boils at a lower temperature and all candy stages shift downward by about 2 F per 1,000 feet. This calculator lets you select your candy stage or enter a custom target temperature, enter your elevation, and get the adjusted temperature range to use in your kitchen. It also shows you exactly what candy the stage is used for and the cold-water test description for that stage.
Altitude adjustment formula
Adjusted temperature = Sea-level temperature - (elevation in feet / 1,000) * 2
Example: Soft ball at 5,000 ft = 235 - (5,000 / 1,000 * 2) = 235 - 10 = 225 F
The 2 F per 1,000 feet rule is derived from the fact that the boiling point of water decreases by approximately 1.8-2 F for every 1,000 feet of elevation gain. Since candy stages are defined relative to boiling point, the same offset applies.
Full candy stage reference
- Thread (230-235 F): Syrup forms thin threads. Used for syrups.
- Soft Ball (235-240 F): Syrup forms a soft, pliable ball. Used for fudge and pralines.
- Firm Ball (245-250 F): Ball holds its shape. Used for caramels.
- Hard Ball (250-265 F): Ball is hard and chewy. Used for nougat and marshmallows.
- Soft Crack (270-290 F): Syrup forms flexible threads. Used for taffy.
- Hard Crack (300-310 F): Syrup forms brittle threads. Used for toffee and lollipops.
- Caramel (320-350 F): Sugar begins to brown. Used for caramel sauce and pralines.
Candy temperatures: frequently asked questions
What are the main candy-making temperature stages?
Thread (230-235 F), Soft Ball (235-240 F), Firm Ball (245-250 F), Hard Ball (250-265 F), Soft Crack (270-290 F), Hard Crack (300-310 F), and Caramel (320-350 F). Each stage corresponds to a specific sugar concentration.
Why do I need to adjust candy temperatures at high altitude?
Water boils at a lower temperature at high altitude. The candy temperature stages are defined relative to the boiling point of water. At 5,000 feet, water boils at about 202 F instead of 212 F, so you must reduce target candy temperatures by the same 10 F difference.
How do I adjust candy temperature for altitude?
Subtract 2 F from the target temperature for every 1,000 feet above sea level. At 5,000 feet, reduce all target temperatures by 10 F. So soft ball stage (235-240 F at sea level) becomes 225-230 F at 5,000 feet.
What candy is made at soft ball stage?
Fudge, pralines, and fondant are made at soft ball stage (235-240 F at sea level). At this temperature, a small amount of syrup dropped into cold water forms a soft, pliable ball that flattens when removed.
What is hard crack stage used for?
Hard crack stage (300-310 F at sea level) is used for toffee, brittle, lollipops, and rock candy. Syrup at this stage forms brittle threads when dropped into cold water.
Official sources
- USDA Agricultural Research Service: FoodData Central.
- Colorado State University Extension: High Altitude Food Preparation (9.376).
Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. See our methodology.