Egg Boiling Time Calculator

How to Use the Calculator

1. Select the Egg size that matches your eggs — small, medium, large or extra large. If you are unsure, weigh one egg: most recipes assume large (about 50 g).
2. Enter the Starting temperature of the egg in the number field and choose °C or °F from the unit dropdown. A fridge egg is about 4°C (39°F); an egg sitting on the counter is closer to 18–20°C (64–68°F).
3. Pick your Desired yolk firmness: soft (runny yolk, set white), medium (jammy, just-set yolk) or hard (fully set yolk).
4. Read the Estimated boiling time in minutes and the Suggested cooling step, then start timing only once the water is fully boiling and the eggs are in it.

How Egg Boiling Time Works

An egg cooks when heat from the water travels through the shell and into the white and yolk. The white begins to set at around 63°C (145°F), while the yolk does not thicken until about 65–70°C (149–158°F). That narrow gap between the two is what makes timing so important: a minute or two is the difference between a runny yolk and a firm one.

Two factors dominate how fast an egg heats up. The first is its mass — a bigger egg holds more cold material and simply takes longer to warm through, which is why the calculator adds time for extra-large eggs and subtracts it for small ones. The second is the starting temperature: an egg taken straight from the fridge carries a pocket of cold at its centre that must be overcome before the yolk starts to cook, so it needs roughly 0.07 minutes (about 4 seconds) more for every degree below room temperature, and correspondingly less when it is warm.

The estimates assume the classic method: the egg is lowered into water that is already at a rolling boil, and timing starts at that moment. This is why the numbers are short — if you put eggs into cold water and bring it to the boil, the eggs cook slowly during the heat-up phase and the timing becomes far less predictable. The results also assume sea level, where water boils at 100°C (212°F). At altitude, water boils cooler and times run longer.

Interpreting the result is straightforward, but treat it as a starting point rather than a law. Egg freshness, how many eggs you cook at once (a big batch cools the water temporarily), burner power and pot shape all nudge the outcome. If your eggs come out slightly under or over, adjust by 30 seconds in the relevant direction next time — timing eggs is a skill you calibrate in two or three attempts.

Assumptions, Limitations and Practical Tips

• Boiling water start: the times count from lowering eggs into already-boiling water at sea level. They do not apply to the cold-water-start method or to steaming.
• Altitude: above about 1,500 m (5,000 ft), water boils below 95°C (203°F). Add roughly half a minute for every 300 m (1,000 ft) of elevation.
• Batch size: dropping six cold eggs into a small pot can pause the boil. Use a pot with enough water (at least 1 cm / ½ in above the eggs) and let it return to a boil quickly before trusting the timer.
• Freshness: very fresh eggs are harder to peel after boiling; slightly older eggs (about a week) release their shells more cleanly. Freshness barely affects timing.
• Safety: if you plan to keep hard-boiled eggs, cool them promptly in ice water and refrigerate within two hours; use within one week.
• Peeling tip: shock the eggs in cold or ice water as soon as the time is up — it stops the cooking, prevents the grey-green ring around hard yolks, and helps the membrane pull away from the shell.

Related Kitchen Calculators

Planning the rest of the meal? The Meat Cooking Time Calculator helps you time roasts and other proteins, the Brine Salt Calculator gets the salt ratio right for pickled eggs, and the Recipe Cost Calculator works out what a dish actually costs to make. For ingredient swaps while you cook, try the Ingredient Substitution Calculator.