Perfect Egg Calculator
• Sea Level: 0m
• Denver: ~1,600m
• Mexico City: ~2,250m
The Science of Boiling Eggs
Boiling eggs is a deceptively simple process that depends on precise timing and technique. The calculator above will help you achieve your desired egg consistency, but understanding the science behind egg cooking can help you perfect your technique.
What Happens When Eggs Cook?
Egg whites begin to set at 144°F (62°C), while egg yolks start setting at 149°F (65°C). The longer an egg cooks, the more the proteins contract, forcing out water and creating firmer results. This is why timing is critical:
- 4-5 minutes: Whites set, yolks remain runny
- 6-7 minutes: Whites set, yolks become jammy
- 8-10 minutes: Whites and yolks fully set
Egg Boiling Reference Guide
While our calculator provides personalized timings, this reference table gives you general guidelines for different egg sizes starting from room temperature or refrigerated.
| Egg Size | Starting Temp | Runny Yolk | Jammy Yolk | Hard-Boiled |
|---|---|---|---|---|
| Small (<53g) | Room Temp | 4 min | 5 min | 7 min |
| Small (<53g) | Refrigerated | 5 min | 6 min | 8 min |
| Medium (53-63g) | Room Temp | 5 min | 6 min | 8 min |
| Medium (53-63g) | Refrigerated | 6 min | 7 min | 9 min |
| Large (63-73g) | Room Temp | 6 min | 7 min | 9 min |
| Large (63-73g) | Refrigerated | 7 min | 8 min | 10 min |
| Extra Large (>73g) | Room Temp | 7 min | 8.5 min | 10 min |
| Extra Large (>73g) | Refrigerated | 8 min | 9.5 min | 11 min |
Note: These times assume starting with boiling water at sea level. Adjust for altitude using the calculator above.
Professional Egg Boiling Methods
Cold Start Method
Professional chefs often use this for hard-boiled eggs:
- Place eggs in cold water
- Bring to a gentle boil
- Remove from heat, cover
- Let stand 10-12 minutes
- Transfer to ice bath
Best for: Hard-boiled eggs with minimal risk of cracking
Hot Start Method
Used by many restaurant chefs for soft-boiled eggs:
- Bring water to a gentle boil
- Lower eggs with a slotted spoon
- Maintain gentle simmer
- Time precisely (per calculator)
- Transfer immediately to ice bath
Best for: Consistent soft or medium-boiled eggs
Steaming Method
Popular in professional kitchens:
- Bring 1 inch of water to boil in a pot
- Place eggs in steamer basket
- Cover and steam (5-6 min for soft, 10-12 for hard)
- Transfer to ice bath
Best for: Easier peeling, especially with fresh eggs
Sous Vide Method
For perfect consistency:
- Set water bath to 145°F (63°C) for soft, 165°F (74°C) for hard
- Cook for 45 minutes
- Optional: Finish with quick boil to set outer white
Best for: Ultimate precision, never overcooking
Troubleshooting Common Egg Problems
- Green ring around yolk: Occurs when eggs cook too long. The iron in the yolk reacts with hydrogen sulfide from the white. Solution: Use the calculator and don’t overcook.
- Difficult to peel: Fresh eggs are harder to peel. Solution: Use eggs 7-10 days old or add ½ teaspoon baking soda to water.
- Cracked shells during cooking: Usually from temperature shock. Solution: Let refrigerated eggs come to room temperature or add eggs to water gently with a spoon.
- Inconsistent results: Usually from imprecise timing or varying water temperature. Solution: Use the calculator and maintain a gentle simmer, not a rolling boil.
- Undercooked whites with set yolks: Common when starting with very cold eggs. Solution: Use room temperature eggs or add 30 seconds to cooking time.
Egg Storage and Freshness
The age of your eggs affects both cooking time and peelability. Here’s how to check egg freshness:
- Float test: Place an egg in a bowl of water. Fresh eggs sink and lie flat. Older eggs stand upright or float. Floating eggs are likely spoiled.
- Date check: In the US, eggs can be used 3-5 weeks beyond the pack date (printed as a Julian date – the day of the year from 001-365).
- Visual inspection: After cracking, fresh eggs have a plump, rounded yolk that stands tall and thick whites that don’t spread much.
For boiled eggs, store them unpeeled in the refrigerator for up to one week. Peeled eggs should be consumed within 2-3 days.