About the Baking Conversion Calculator
What is the Baking Conversion Calculator?
Using a different cake tin or oven from the recipe? This baking conversion calculator scales ingredients by pan area and adjusts the oven temperature.
Round, square and rectangular pans are all supported.
How to use the Baking Conversion Calculator
- Recipe Temperature (°C) (sample: 180)
- Your Oven (sample: Conventional / OTG (top and bottom heat))
- Recipe Pan Shape (sample: Round)
- Recipe Pan Diameter / Side (cm) (sample: 20)
- Recipe Pan Second Side (cm, rectangle only) (sample: 0)
- Your Pan Shape (sample: Round)
- Your Pan Diameter / Side (cm) (sample: 23)
- Your Pan Second Side (cm, rectangle only) (sample: 0)
- Press Convert for Your Oven and Pan (results also refresh as you type). The result card shows the Ingredient Scale Factor, along with Set your oven to, In Fahrenheit, Gas mark (recipe temperature) and Pan area change.
Formula used
Scale factor = New pan area ÷ Recipe pan area
- Round pan area = π × (diameter ÷ 2)²
- Fan oven = recipe temperature − 20 °C
Worked example
These are the sample values already filled in the calculator above, and the result it returns for them:
| Input | Sample value |
|---|---|
| Recipe Temperature (°C) | 180 |
| Your Oven | Conventional / OTG (top and bottom heat) |
| Recipe Pan Shape | Round |
| Recipe Pan Diameter / Side (cm) | 20 |
| Recipe Pan Second Side (cm, rectangle only) | 0 |
| Your Pan Shape | Round |
| Your Pan Diameter / Side (cm) | 23 |
| Your Pan Second Side (cm, rectangle only) | 0 |
| Result | Value |
|---|---|
| Ingredient Scale Factor | 1.3225× |
| Set your oven to | 180°C |
| In Fahrenheit | 356°F |
| Gas mark (recipe temperature) | 4 |
| Pan area change | 32% |
| Baking time | If you keep the same batter, it will be thinner – check 5–10 minutes early |
| Egg rule | Scale eggs by the factor and round; beat an extra egg and use part of it if needed |
Tips for using the Baking Conversion Calculator
- Microwave convection modes behave like fan ovens – reduce the temperature.
- Fill cake tins no more than two-thirds full.