What this calculator does
Egg boiling time works out boiling time for an egg by size and doneness, scaled from a large-egg baseline. Enter your own figures above and the answer updates as you type: nothing is fixed in the code, so the result reflects exactly the numbers you supply.
The formula this calculator evaluates is printed under the tool and explained below, so you can check the working by hand or reuse it in a spreadsheet.
The formula
FormulaTime = baseline time (large egg) × (egg mass ÷ 57 g)^(2/3), the surface-area-to-volume scaling for heat conduction
The inputs explained
| Field | What to enter |
|---|---|
| Egg size (USDA) | Choose from Small (43 g), Medium (50 g), Large (57 g), Extra large (64 g), Jumbo (71 g). |
| Doneness | Choose from Soft-boiled, runny yolk, Medium, jammy yolk, Hard-boiled, fully set. |
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How the answer changes with egg size (usda)
Every other input is held at the calculator’s starting values. Select any row to load that scenario.
How the answer changes with egg size (usda)
| Egg size (USDA) | Boiling time | In minutes | Baseline used |
|---|---|---|---|
| Small (43 g) | 7:27 | 7.46 min | Large egg (57 g), added to already-boiling water |
| Medium (50 g) | 8:15 | 8.25 min | Large egg (57 g), added to already-boiling water |
| Large (57 g) | 9:00 | 9.00 min | Large egg (57 g), added to already-boiling water |
| Extra large (64 g) | 9:43 | 9.72 min | Large egg (57 g), added to already-boiling water |
| Jumbo (71 g) | 10:25 | 10.42 min | Large egg (57 g), added to already-boiling water |