Advertisement
100% x 90

Ideal Egg Boiling Calculator

Calculate perfect egg boiling times based on scientific principles and altitude

Egg Cooking Setup

Choose the size of your egg

Initial temperature of the egg

Altitude affects water boiling point (0m = sea level)

Choose your preferred level of doneness

Environmental Conditions

Air Pressure:
1013.3 hPa
Boiling Point:
100.0°C
Egg Temperature:
4°C

Egg Boiling Times

Quarter-boiled
0min 0sec
Very soft white, liquid yolk
Soft-boiled
0min 0sec
Firm white, runny yolk
Medium-boiled
0min 0sec
Firm white, slightly runny center
Hard-boiled
0min 0sec
Firm white, fully set yolk

Formula: Charles Williams formula for heat diffusion in eggs

Target Temperature: 65°C for soft-boiled

Mass Factor: Egg mass = 57g

Cooking Analysis

Example Calculation

Perfect Soft-Boiled Egg

Egg: Medium size (57g) from fridge (4°C)

Location: Sea level (0m altitude)

Boiling point: 100°C

Target: Soft-boiled (65°C internal)

Result

Using Charles Williams formula:

t = m^(2/3) × K × log((ywr(T_egg - T_water))/(T - T_water))

Cooking time: 6 minutes 44 seconds

Advertisement
100% x 250

Doneness Guide

¼

Quarter-boiled

60°C internal

Very soft white, liquid yolk

S

Soft-boiled

65°C internal

Firm white, runny yolk

M

Medium-boiled

70°C internal

Firm white, slightly runny center

H

Hard-boiled

75°C internal

Firm white, fully set yolk

Pro Cooking Tips

Use generous amount of water to maintain temperature

Add salt to prevent eggs from cracking

Start timer when eggs enter boiling water

Immediately cool in cold water to stop cooking

Room temperature eggs are less likely to crack

The Science Behind Perfect Egg Boiling

Heat Diffusion in Eggs

When an egg is placed in boiling water, heat transfers from the shell through the white to the yolk. The egg white coagulates at a lower temperature (60-65°C) than the yolk (65-70°C), allowing for different textures based on the internal temperature reached.

Charles Williams Formula

t = m^(2/3) × K × log((ywr(T_egg - T_water))/(T - T_water))

  • t: Cooking time (minutes)
  • m: Mass of egg (grams)
  • K: Thermal diffusivity factor (0.0054)
  • ywr: Yolk to white ratio (0.76)
  • T_egg: Initial egg temperature
  • T_water: Boiling water temperature
  • T: Target internal temperature

Altitude Effects

At higher altitudes, atmospheric pressure decreases, causing water to boil at lower temperatures. For every 300 meters of elevation, the boiling point drops by approximately 1°C, requiring longer cooking times to reach the same internal temperatures.

Temperature Guidelines

Soft-boiled: 65°C (149°F)

Firm white, runny yolk

Hard-boiled: 75°C (167°F)

Fully set, avoid green ring

Note: Above 77°C, sulfur in the white reacts with iron in the yolk, creating an unappetizing green ring.

Pro Egg Peeling Hacks

Blow Method

Crack both ends of the cooled egg and blow firmly through one end. The egg will slide out of the shell!

🎯 Works best with room temperature eggs

Shake Method

Place the cooked egg in a container with water, close tightly, and shake vigorously for 10-15 seconds.

🥤 The water helps separate the shell

Roll Method

Crack the egg and roll it on the counter for a few seconds, then peel under cold running water.

💧 Cold water helps shell removal
Advertisement
100% x 250