Candy Temperature Guide Calculator
Find sugar temperature in °F and °C for every candy stage — thread, soft ball, firm ball, hard ball, soft crack, and hard crack — with altitude adjustments.
Candy making is one of the most chemistry-dependent forms of cooking. As you heat sugar syrup, water evaporates and the sugar concentration rises — each concentration level produces a distinct texture when cooled.
Why temperature determines texture: At low temperatures, remaining water keeps sugar pliable and soft. At high temperatures, nearly all water is driven off, leaving pure concentrated sugar that hardens as it cools.
The temperature-to-stage relationship:
| Stage | °F | °C | Water Remaining | Texture When Cooled | Products |
|---|---|---|---|---|---|
| Thread | 230–235 | 110–112 | ~20% | Thin syrupy threads | Simple syrup, glaze |
| Soft ball | 235–240 | 112–116 | ~15% | Soft, pliable ball | Fudge, fondant, pralines |
| Firm ball | 245–250 | 118–121 | ~13% | Holds shape but bends | Caramels, marshmallows |
| Hard ball | 250–265 | 121–130 | ~8% | Rigid but chewy | Nougat, divinity, rock candy |
| Soft crack | 270–290 | 132–143 | ~5% | Separates into threads, bends | Taffy, butterscotch |
| Hard crack | 300–310 | 149–154 | ~1% | Brittle, snaps cleanly | Toffee, brittle, lollipops |
| Light caramel | 320–340 | 160–171 | ~0% | Amber, bitter note | Light caramel sauce |
| Dark caramel | 340–360 | 171–182 | ~0% | Dark amber, complex | Crème brûlée topping |
Temperature conversion:
°F = (°C × 9/5) + 32
°C = (°F − 32) × 5/9
Altitude adjustment: critical: Water boils at lower temperatures at higher elevations (about 1°F / 0.5°C less per 500 ft / 150 m of elevation). Since candy stages are defined by water evaporation, you must lower your target temperature accordingly. At 5,000 ft (1,524 m): subtract approximately 10°F / 5.5°C from all stage temperatures.
The cold-water test (no thermometer needed): Drop a small amount of hot syrup into a cup of ice water and observe the texture by hand. This traditional method is still reliable — professional candy makers use it to double-check thermometer readings.
Equipment tip: Use a candy thermometer clipped to the side of the pot without touching the bottom (the bottom is hotter than the syrup). Digital instant-read thermometers work too but require quick readings as temperatures climb fast above 300°F.