How long to hard boil an egg
Hard · Large · Fridge
Get the ice bath ready. Yolks keep setting after the pan comes off.
Duck, quail, altitude and more
Hard boiled egg times for your egg size, starting temperature and altitude, with a timer. Fully set yolk with no grey ring.
The short answer
A large, fridge-cold egg lowered into boiling water at sea level needs 12 min 30 sec for hard boiled, fully set. Completely firm. Pull it at this point and the yolk stays yellow, not grey.
| Egg size | From the fridge | Room temperature | Cold water start |
|---|---|---|---|
| Small | 10 min 30 sec | 9 min | 8 min |
| Medium | 11 min 30 sec | 10 min | 9 min |
| Large | 12 min 30 sec | 11 min | 9 min 45 sec |
| Extra large | 13 min 45 sec | 11 min 45 sec | 10 min 30 sec |
| Jumbo | 14 min 30 sec | 12 min 45 sec | 11 min 15 sec |
Hard boiled, fully set at sea level. Use the calculator above to adjust for altitude.
What a hard boiled egg is for
Packed lunches, picnics and anything that has to travel. The yolk is completely firm, which means the egg can be carried, peeled hours later and eaten with one hand. It is also the doneness food safety guidance points to for anyone pregnant, elderly, very young or immunocompromised, because both white and yolk are fully set.
How to tell it worked
The yolk should be pale yellow and completely solid, and it should be yellow all the way to the edge. A grey or faintly green ring means it went past done. That ring is iron sulphide, it is harmless, and it is the clearest sign that the egg was in the water too long or cooled too slowly.
The usual mistake
Cooking longer for safety. Nothing improves after the yolk sets at about 82 degrees, and every minute past that drives out moisture and pushes the sulphur reaction along. If you are boiling a batch to keep in the fridge, the time is the same and the ice bath matters more, not less.
Other boiling times
Egg guides
Common questions
Should the eggs go into cold water or boiling water?
Boiling water gives you far more control, because the clock starts at a known temperature. Cold-water starts work too, but the time depends on how fast your hob heats the pan, so treat the cold-start numbers as a guide and check one egg. Pick "cold-water start" above and the times adjust for you.
Why does my timing keep coming out wrong?
Usually egg size or starting temperature. A jumbo egg needs about two minutes longer than a small one for the same result, and a fridge-cold egg needs roughly a minute and a half longer than one left on the counter. Altitude matters too: above about 1,500 m the water boils below 100 °C, so everything takes longer.
How do I stop the cooking at the right moment?
Move the eggs straight into iced water. The shell holds a lot of heat and the yolk keeps setting for a minute or two after you drain the pan, which is what turns a jammy yolk chalky. An ice bath also contracts the egg away from the shell and makes peeling far easier.
What causes the grey-green ring around the yolk?
Overcooking. Iron in the yolk reacts with sulphur in the white and forms iron sulphide. It is harmless but it tastes flat and chalky. Use the time above rather than a generic one and cool the eggs immediately and you will not see it.
Egg times come from the thermal-diffusion equation for a spherical egg published by Charles D. H. Williams (University of Exeter), calibrated so a large fridge-cold egg at sea level matches the times cooks actually use. Size, starting temperature and altitude then follow from the physics. Treat the result as a very good starting point, not a guarantee, because pans, hobs and eggs all vary.