Egg Boiling Time Calculator
Getting perfectly cooked boiled eggs every time comes down to two things: time and temperature control. The yolk texture at different cooking times goes from liquid and runny at 6 minutes, to jammy and partially set at 9-10 minutes, to fully firm at 12-14 minutes. Egg size, starting temperature (room temp vs cold from fridge), and your altitude all affect the result. This calculator accounts for all three variables. It uses the standard culinary boiling times for large eggs started in already-boiling water, then adjusts for egg size (small eggs cook faster; jumbo eggs cook slower) and starting temperature (add 1 minute if cold from fridge). An altitude adjustment adds time for elevations above sea level where water boils at a lower temperature.
Boiling time formula
Base time = doneness base (soft: 6 min, medium: 9 min, hard: 12 min)
Size adjustment: small -1 min, medium -0.5 min, large 0, XL +0.5 min, jumbo +1 min
Cold start adjustment: +1 minute
Altitude adjustment: +(elevation / 1,000) * 1 minute
Total = base + size adj + cold adj + altitude adj
Times assume eggs are lowered into already-boiling water. Immediately transfer to ice water when the timer ends to stop cooking.
Boiling tips for perfect eggs
- Use a pin or thumbtack to poke a small hole in the wider end of the egg before boiling to release the air pocket and prevent cracking.
- Lower eggs gently into the water with a spoon to prevent cracking from impact.
- Keep the water at a gentle boil, not a rolling boil, which can make eggs bounce and crack.
- Ice bath immediately stops cooking and makes peeling dramatically easier.
- Store hard-boiled eggs unpeeled in the refrigerator for up to 1 week.
Egg boiling: frequently asked questions
How long do I boil an egg for a runny yolk?
For a large egg starting at room temperature, boil for 6 minutes for a runny yolk (soft boiled). If starting from the refrigerator (cold), add 1 minute. Remove and transfer to ice water immediately to stop cooking.
What is the difference between soft boiled and medium boiled eggs?
Soft boiled (6 minutes) has a fully set white and a liquid, runny yolk. Medium boiled (9-10 minutes) has a fully set white and a jammy, partially set yolk that is soft but not runny. Hard boiled (12-14 minutes) has both a fully set white and fully set, dry yolk.
Why should I start eggs in cold water vs boiling water?
Starting in cold water produces more even heating and gentler cooking, reducing the chance of cracking. Starting in boiling water gives more precise timing and is preferred for soft-boiled eggs where the exact texture matters most.
How do altitude and boiling point affect egg boiling time?
Water boils at lower temperatures at high altitude: about 202 F at 5,000 feet vs 212 F at sea level. Lower boiling temperature means slower cooking. Add approximately 1 minute per 1,000 feet above sea level.
How do I peel hard boiled eggs easily?
Immediately transfer cooked eggs to an ice bath for at least 5 minutes. The rapid temperature change contracts the egg inside the shell, making peeling much easier. Gently rolling the egg on a hard surface also helps crack the shell evenly before peeling.
Official sources
- USDA Agricultural Marketing Service: Shell Egg Grades and Standards.
- USDA Food Safety and Inspection Service: Shell Eggs from Farm to Table.
Reviewed by the CalculatorHub team, edited by James Graham, 14 June 2026. See our methodology.