Perfect Egg Timing Calculator
Get exact cooking times for soft, medium, and hard boiled eggs based on egg size, starting temperature, and altitude.
The perfect boiled egg is a matter of precise timing and temperature control. The proteins in egg whites and yolks coagulate at specific temperatures, and controlling how much heat penetrates the egg determines whether you get a runny yolk, a jammy center, or a fully cooked firm yolk.
Egg Protein Temperature Reference
Understanding when egg proteins set helps explain the timing:
- 63°C (145°F): Egg white begins to set slowly
- 71°C (160°F): Egg white is fully set but still tender
- 70°C (158°F): Yolk begins to thicken
- 77°C (170°F): Yolk is fully solid but still moist
- 85°C+ (185°F+): Yolk becomes crumbly, grey-green ring may form
Why Starting Temperature Matters
Eggs taken directly from the refrigerator (typically 4°C / 39°F) take 1–2 minutes longer to cook than eggs at room temperature (20°C / 68°F). Always factor this in to avoid under- or over-cooked yolks.
Altitude Effects
At high altitudes, water boils at lower temperatures, which slows the cooking process. At 2,000 m (6,560 ft), water boils at ~93°C (199°F), and eggs require roughly 1 minute of extra cooking time per 1,000 m of altitude above sea level.
Cooking Time Guidelines (Large Eggs, Sea Level)
| Style | From Room Temp | From Fridge |
|---|---|---|
| Soft boiled (runny white, runny yolk) | 4–5 min | 6–7 min |
| Soft boiled (set white, runny yolk) | 6–7 min | 7–8 min |
| Medium / jammy (set white, jammy yolk) | 9–10 min | 10–11 min |
| Hard boiled (fully set, moist yolk) | 12–13 min | 13–14 min |
| Hard boiled (firm, dry yolk) | 14–15 min | 15–16 min |
Ice Bath After Cooking
Always transfer cooked eggs immediately to an ice water bath for 5 minutes. This stops the cooking process precisely and makes peeling significantly easier. Without this step, carryover heat continues cooking the egg for 1–2 extra minutes.