How Long to Hard-Boil Eggs

The most common mistake is believing one time works for every egg. It doesn't. Egg size, starting temperature, and altitude all shift the clock. For a large egg from the fridge dropped into boiling water, 7 minutes gives a firm yolk and fully set white. That is your baseline. Adjust from there.

Here is one reliable set of times, an explanation of why the green ring forms and how to stop it, and how long hard-cooked eggs keep in the fridge. No formulas. No conflicting charts.

Lower eggs into already-boiling water. This is the method the American Egg Board uses and the one Serious Eats tested in time-lapse. It gives consistent results because the timing starts at the same cooking temperature every time.

Use large eggs straight from the refrigerator. Bring a saucepan of water to a rolling boil. Gently lower the eggs with a slotted spoon to avoid cracking from thermal shock. Start your timer immediately.

Times for Large Eggs, Hot Start

• Very soft, runny yolk: 4 minutes
• Soft, slightly thickened yolk: 5 minutes
• Medium, jammy yolk: 6 minutes
• Hard, fully set yolk: 7 minutes
• Very hard, crumbly yolk: 8 minutes

After the time is up, transfer eggs immediately to an ice water bath to stop cooking. If you skip the ice bath, the residual heat will push the doneness 30 to 60 seconds past your target. The ice bath also prevents the green ring and improves peelability.

Place eggs in cold water, bring to a boil, then time from the boil. Serious Eats found that cold-start eggs peel significantly easier than hot-start eggs. The trade-off is precision: you are timing from a variable point (when the water reaches a boil) rather than from a fixed one.

Because the eggs heat gradually during the temperature rise, cold-start times are longer. For large eggs from the fridge, the total time from the moment the water reaches a rolling boil is:

• Very soft: 6 minutes
• Soft: 7 minutes
• Medium: 8 minutes
• Hard: 9 minutes
• Very hard: 10 minutes

The cold-start extra time over a boiling start is roughly 2 minutes across all doneness levels. If you are boiling eggs for meal prep and peeling matters more than exact yolk set, use the cold start.

The green ring between the yolk and white is iron sulfide. Harold McGee explains in On Food and Cooking that it forms when prolonged heat causes iron in the yolk to react with sulfur in the white. The ring is harmless, but it signals that the egg was overcooked or cooled too slowly.

Prevention is simple: cool the eggs immediately after cooking. Plunge them into an ice water bath for at least 10 minutes. The rapid temperature drop stops the iron-sulfur reaction before the ring can form. If you let eggs cool in the hot water or at room temperature, you will get the green ring every time.

The ring also appears when eggs are boiled too long beyond the hard-cooked stage. Stick to the times above and do not let the eggs sit in hot water after the timer goes off.

To boil a dozen eggs at once, use a pot large enough to hold them in a single layer. Cover with at least 1 inch of cold water. Bring to a rolling boil, then follow the cold-start method above. Do not crowd the pot; if eggs stack, the ones on top cook unevenly.

The American Egg Board method works for batches: place eggs in a single layer, cover with 1 inch water, bring to a boil, remove from heat, and cover. Let stand for 9 minutes for firm hard-cooked large eggs. This is a reliable hands-off approach for meal prep.

For consistent results across different egg sizes, know your USDA egg size grade. A jumbo egg (30 oz per dozen) needs about 30 seconds more than a large egg for the same doneness. A medium egg (21 oz per dozen) needs about 30 seconds less.

The USDA FSIS egg storage chart says hard-cooked eggs in the shell keep for 1 week when refrigerated at 40 °F (4.4 °C) or below. Peeled eggs also keep for 1 week, but they must be stored in a covered container to prevent absorbing fridge odors.

Raw shell eggs in the shell can be stored 3 to 5 weeks from the pack date (the Julian date on the carton), but once cooked, the clock resets to that 1-week window. Do not leave hard-cooked eggs at room temperature for more than 2 hours.

For vulnerable groups, the elderly, infants, pregnant women, and immunocompromised people, the USDA FSIS and FDA recommend cooking eggs until both the yolk and white are firm. Runny yolks carry a risk of Salmonella. If you are cooking for someone in a vulnerable group, use the 8-minute (very hard) time for large eggs.

For deviled eggs, use the hard-cooked (7-minute) time for large eggs. The yolk needs to be fully set to hold its shape when halved. A medium-boiled jammy yolk will not slice cleanly. The cold-start method makes peeling easier, which matters for deviled eggs where appearance counts.

For egg salad, use the very hard (8-minute) time. The yolk should be crumbly so it mixes evenly with mayonnaise and seasonings. A soft or medium yolk will create an uneven texture. Older eggs, 7 to 10 days from packing, peel more easily than very fresh eggs, making them the better choice for both recipes.