Kitchen know-how
Cooking conversions.
All in one place.
Quick tables for air fryers, ovens, slow cookers and everyday measurements.
01 / Oven & air fryer
Fan oven → air fryer
Find your temperature on the left, then your cooking time on the right. Read backwards to convert an air-fryer recipe to an oven recipe.
| Fan oven | Air fryer*Same temperature to start | ConventionalNo fan | Gas mark | Conventional °F | Oven → air fryer timeShorten by about 20% |
|---|---|---|---|---|---|
| 120°C | 120°C* | 140°C | 1 | 275°F | 10 min8 min 15 min12 min 20 min16 min 25 min20 min 30 min24 min 40 min32 min 50 min40 min 60 min48 min Independent of the temperature rows. |
| 130°C | 130°C* | 150°C | 2 | 300°F | |
| 140°C | 140°C* | 160°C | 3 | 325°F | |
| 160°C | 160°C* | 180°C | 4 | 350°F | |
| 170°C | 170°C* | 190°C | 5 | 375°F | |
| 180°C | 180°C* | 200°C | 6 | 400°F | |
| 200°C | 200°C* | 220°C | 7 | 425°F | |
| 210°C | 210°C* | 230°C | 8 | 450°F |
Temperature and time are separate lookups. For example: 180°C fan for 30 minutes → approximately 180°C air fryer for 24 minutes. Start checking before the estimated finish time.
*Air fryers vary. This guide starts at the fan-oven temperature (20°C below conventional). Some models need a lower setting: follow your manual or a tested recipe first. Stay within your appliance’s temperature limits.
Fan ↔ conventional: use the equivalent temperature in the table and keep the recipe time as your starting point. Air fryer → oven: read the time pairs backwards (about 25% longer). Timings exclude preheating. °F values are rounded recipe equivalents. Gas marks refer to conventional gas ovens.
02 / Slow cooker & oven
Slow cooker ↔ oven
For covered stews, casseroles and braises only. Read across in either direction.
| Fan oven140°C | Conventional oven160°C / gas 3 | Slow cooker Low | Slow cooker High |
|---|---|---|---|
| 1½–2 hours | 1½–2 hours | 6–8 hours | 3–4 hours |
| 2–3 hours | 2–3 hours | 8–10 hours | 4–6 hours |
Oven → slow cooker: for a liquid-rich stew, try around a third less added stock or water; follow your manual’s liquid and filling guidance. Slow cooker → oven: use a covered ovenproof casserole and top up with hot liquid if needed.
Important slow-cooker tips
These ranges vary with meat cut, piece size and quantity; use a tested recipe where possible. They are not suitable for crisp roasts, baking, quick-cooking fish, rice or pasta dishes. Thaw meat first. Prepare dried beans according to the packet; raw dried kidney beans must not be cooked only in a slow cooker. Use a slow-cooker insert in an oven only if its manufacturer allows it.
03 / Weights & measures
Weights, cups & spoonfuls
Read across for each ingredient. Weights are approximate; use scales for baking.
| Ingredient | 1 cup | ½ cup | 1 tbsp |
|---|---|---|---|
| Plain / all-purpose flour | 120g | 60g | 7.5g |
| Granulated sugar | 198g | 99g | 12.4g |
| Butter | 227g | 114g | 14.2g |
| Rolled oats | 113g | 57g | 7.1g |
| Water | 237g | 118g | 14.8g |
US cup ≈ 237ml; 16 US tbsp = 1 US cup. Flour is spooned in and levelled, not packed; oats are measured dry and butter is measured without air gaps. Ingredient values follow King Arthur Baking’s chart; water uses volume equivalence. Half-cup and tablespoon weights are calculated and rounded.
Convert any amount: grams ÷ grams per cup = cups. For example, 180g plain flour ÷ 120 = 1½ US cups. For tablespoons, divide by the ingredient’s grams per tablespoon instead. Do not use one ingredient’s conversion for another.
| Metric | Imperial (approx.) |
|---|---|
| 28.35g | 1oz |
| 100g | 3½oz |
| 250g | 8.8oz |
| 454g | 1lb |
| 500g | 1lb 1.6oz |
| 1kg | 2lb 3.3oz |
| Measure | Millilitres |
|---|---|
| 1 metric teaspoon | 5ml |
| 1 metric tablespoon | 15ml |
| 1 US recipe cup | About 237ml |
| 1 metric cup | 250ml |
| 1 UK pint | About 568ml |
| 1 UK fluid ounce | About 28.4ml |
| 1 US fluid ounce | About 29.6ml |
Check the recipe’s country: US cups are about 237ml, metric cups are 250ml, and a traditional UK imperial cup is about 284ml. Australian tablespoons are 20ml; metric tablespoons used here are 15ml. US tablespoons are about 14.8ml. Use measuring spoons, not cutlery. Fluid ounces measure volume; ounces measure weight.
Scaling a recipe up or down
New servings ÷ original servings = your ingredient multiplier. Going from 4 servings to 6? Multiply ingredients by 1.5. Cooking time does not scale in the same way: dish depth, meat size and appliance capacity matter. Taste and adjust seasoning, and check that everything is cooked through.