How to halve a recipe

Quick conversion table

Weights and volumes

Use digital scales for small amounts of flour, sugar and butter. For liquids, a tablespoon measure is often more accurate than reading 40–75 ml at the bottom of a large jug. Keep units consistent before dividing.

Eggs

Beat the egg until evenly combined, weigh it, then use half by weight. Cover and refrigerate the unused beaten egg promptly and use it in a thoroughly cooked dish within the relevant official storage guidance for your location.

Baking tins and pan area

Halving ingredients while keeping the original tin makes a shallow bake. Aim for roughly half the base area so the depth remains similar. For rectangular tins, multiply length by width; for round tins, comparing the square of each diameter gives a useful area ratio.

Example: an 18 cm round tin has about half the area of a 25 cm round tin, making it a reasonable starting point for half a batch.

Oven temperature

Keep the original oven temperature unless the recipe or a tested source says otherwise. A smaller quantity changes depth and cooking duration, not the temperature the structure needs.

Cooking time

Do not automatically halve it. Begin checking earlier—often around two-thirds of the original time—then rely on the same doneness cues: colour, internal texture, tenderness or temperature where the original recipe specifies one.

Seasoning

Start with slightly less than half of strongly flavoured ingredients such as salt, chilli and concentrated extracts. Taste near the end and adjust. Surface evaporation and pan size can change how intense a smaller batch becomes.

Yeast and chemical leavening

Weigh yeast, baking powder and bicarbonate of soda accurately; simply halve the stated weight. Avoid rounded spoon measures. Dough rising is governed by dough condition and room temperature, so watch the dough rather than halving the proving time.

Sauces and reductions

Use a smaller pan to maintain depth and check sooner. A wide original pan can evaporate a half batch too quickly, concentrating salt or sugar before the other ingredients are ready.

Unused ingredients

• Label leftovers with the ingredient and date.
• Refrigerate perishable ingredients promptly.
• Freeze only where suitable guidance exists, in quantities useful for a future recipe.
• When in doubt about storage safety, follow current official food-safety advice rather than a general recipe conversion.

Final checklist

1. Convert all quantities before beginning.
2. Choose a vessel that preserves depth.
3. Keep the temperature, but check earlier.
4. Season cautiously and taste.
5. Write down successful changes for next time.