π¬ Sugar Syrup Stage Calculator
Every candy stage from temperature.
How to Use This Calculator
Enter your syrup temperature and altitude. The calculator identifies the candy stage, shows the adjusted target range for your altitude, and lists what each stage is used for.
Sugar Stages
Hard ball 250-266 F | Soft crack 270-290 F | Hard crack 300-310 F
Caramel 320-350 F | Altitude adjustment: -1 F per 500 ft
As water boils off, the syrup temperature climbs and sugar concentration rises. Each stage is just a sugar percentage: soft ball is about 85 percent sugar, hard crack about 99 percent. The cold-water test works because the syrup firmness in cold water mirrors its firmness at room temperature.
Worked Example
Syrup at 240 F, sea level: soft ball stage, ideal for fudge. At 5,000 feet, subtract 10 F, so your thermometer target for fudge becomes 225 to 235 F.
Cold Water Test
Before thermometers, candy makers used the cold water test: drop syrup into ice water and feel the result. Thread stage forms threads, soft ball forms a squishy ball, hard ball holds shape but is pliable, and hard crack snaps. This calculator's temperatures match these classic tests. At high altitude, subtract 2 F per 1,000 feet because water boils lower.
Avoiding Crystallization
Sugar crystals on the pan wall can seed the whole batch and turn it grainy. Wash down the sides with a wet pastry brush as the syrup heats. Do not stir once it boils; agitation encourages crystals. A tablespoon of corn syrup or lemon juice interferes with crystal formation and is insurance for caramels and fudge.
High Altitude Candy
Water boils lower at altitude, so candy stages shift down too: subtract about 2 F per 1,000 feet of elevation. A Denver cook making fudge targets 234 F instead of 238 F. Syrup thermometers with adjustable clips make this easy; just recalibrate against boiling water at your altitude.
Frequently Asked Questions
What temperature is the soft ball stage?
235 to 245 F (113 to 118 C). Drop syrup in cold water and it forms a soft ball that flattens when removed. This is the stage for fudge, pralines, and fondant.
What is the hard crack stage used for?
300 to 310 F (149 to 154 C). Syrup forms brittle threads that snap. This is the stage for lollipops, brittles, and pulled candy. Work quickly because sugar burns fast past 320 F.
Why did my candy not set?
Almost always undercooking. Even 5 degrees low on fudge leaves it soupy. Calibrate your thermometer in boiling water first: it should read 212 F at sea level, and you adjust all targets by the difference.
Do I need to adjust candy temps for altitude?
Yes. Water boils lower as altitude rises, about 1 F lower per 500 feet. Subtract the same amount from every candy target. At 5,000 feet, soft ball becomes 225 to 235 F.
What is the difference between light and dark caramel?
Light caramel (320 to 335 F) is sweet and buttery. Dark caramel (340 to 350 F) adds bitter, complex notes. Past 350 F it burns and turns acrid. Color deepens fast, so pull it just before your target shade.