Egg Boiling Time Calculator

The Science of Boiling Eggs

Why Starting Temperature Matters

A fridge-cold egg starts at 4°C instead of 20°C. The extra thermal energy needed to reach setting temperature (around 63–70°C for whites, 70°C for yolks) adds approximately 1–2 minutes to cooking time compared to a room-temperature egg.

Altitude Adjustment

Water boils at lower temperatures at altitude: 100°C at sea level, 95°C at 2,000m, 90°C at 3,000m. Lower boiling temperatures mean eggs take longer to cook — add approximately 1 minute per 300m above 1,000m.

The Ice Bath

Immediately transferring boiled eggs to ice water stops the cooking process, preventing the grey-green ring that forms around the yolk when overcooked. It also makes peeling significantly easier by contracting the egg away from the shell.