Sugar syrup stages at sea level

Stage	°F	°C	Cold-water test	Used for
Thread	223–235	106–113	Drips into thin threads	Syrups, candied fruit, glazes
Soft ball	235–240	113–116	Soft ball that flattens when removed	Fudge, pralines, fondant
Firm ball	242–248	117–120	Firm ball that holds its shape	Caramels
Hard ball	250–265	121–129	Hard ball, still slightly pliable	Nougat, marshmallows, divinity, gummies
Soft crack	270–290	132–143	Threads that bend before breaking	Saltwater taffy, butterscotch
Hard crack	300–310	149–154	Brittle threads that snap	Toffee, brittle, lollipops, hard candy
Caramel	320–350	160–177	Syrup turns golden to deep amber	Caramel sauce, spun sugar, praline brittle

Stage ranges follow standard references such as the Exploratorium's candy-making stages and university extension guidance. Individual recipes may target a specific degree within a range. Follow the recipe, adjusted for altitude.

Why altitude changes candy temperatures

Candy stages depend on how much water has boiled out of the syrup. Higher up, water boils at a lower temperature, about 1 °F lower for every 500 feet, so syrup reaches each stage at a lower reading too. The standard fix, recommended by university extension services, is to subtract 1 °F from the recipe's temperature for every 500 feet above sea level (2 °F per 1,000 feet). At 5,000 feet, a fudge recipe that says 236 °F should come off the heat at about 226 °F.

Check your thermometer first

Candy thermometers are often off by a few degrees, and a few degrees is the difference between fudge and a brick. To test yours, clip it in a pot of boiling water for a few minutes and read it. Then choose "My thermometer's boiling-water reading" above and enter the number. The calculator shifts every target by the same amount, which corrects for your altitude and your thermometer at once.

Tips for candy success

Use a heavy pot that's large enough, because boiling sugar foams up.
Read at eye level, with the thermometer bulb fully in the syrup but not touching the bottom of the pot.
Prevent crystals: once the sugar dissolves, stop stirring (unless the recipe says otherwise), and brush the pan sides with a wet pastry brush.
Humid days are harder. Sugar absorbs moisture from the air, so many cooks cook a degree or two higher on very humid days.
Be careful. Sugar syrup can be well above 300 °F and sticks to skin. Keep children and pets away from the stove.

Frequently asked questions

What temperature is soft ball stage?

235–240 °F (113–116 °C) at sea level. It's used for fudge, fondant and pralines. Subtract 1 °F per 500 feet of altitude.

What temperature is hard crack?

300–310 °F (149–154 °C) at sea level, used for toffee, brittle and lollipops.

Can I make candy without a thermometer?

Yes, with the cold-water test. Drop a little syrup into very cold water and check the texture against the chart above. A thermometer is more precise, especially for fudge and caramels, where a few degrees matter.