Oven Temperature Converter

Gas Mark is a temperature scale for gas ovens developed in the United Kingdom, ranging from Gas Mark ¼ (very slow, 225°F/107°C) to Gas Mark 10 (very hot, 500°F/260°C). It was standardized for use in British cookbook recipes and gas appliance calibration. Modern electric ovens in the UK typically list both Celsius and the approximate Gas Mark equivalent. Gas Mark 4 (350°F/180°C) is the most common baking temperature.

Fan-assisted (convection) ovens circulate hot air with a fan, making them approximately 25°F (14°C) hotter than the set temperature compared to a conventional oven. This means a fan oven set to 325°F effectively cooks like a conventional oven at 350°F. When following a conventional recipe, either reduce your fan oven temperature by 25°F or reduce cooking time by 15–20%. Most modern ovens have both conventional and fan settings.

British recipes were historically written for Gas Mark or Celsius-based ovens, and older British cookbooks often used lower temperatures. Additionally, British ovens (especially Aga-style range cookers) are calibrated differently. When converting a British recipe, ensure you are using the correct temperature scale — 180°C (356°F) is the most common British moderate baking temperature, equivalent to American 350°F.

Moderate heat is 325–375°F (163–190°C) or Gas Mark 3–5. This range is used for the majority of baking — cakes, cookies, muffins, casseroles, and most roasted meats. Recipes that say 'moderate oven' without specifying a temperature generally mean 350°F (180°C). A 'hot oven' is 400–450°F, while a 'very hot oven' is 475°F or above.

Use a separate oven thermometer (available for $5–15) placed in the center of the oven. Many ovens are off by 25–50°F from the dial setting. Ovens that have a hot spot at one side or back are also common. If your baked goods consistently over or underbrown, measure with a thermometer and adjust the dial accordingly. Oven thermometers can save significant frustration and wasted ingredients.

Artisan and crusty breads are baked at 450–500°F (232–260°C, Gas Mark 8–9) — the high heat creates rapid oven spring (initial rise) and a crispy, caramelized crust. Sandwich breads and soft rolls use 350–375°F. Enriched breads (brioche, challah) use 325–350°F to prevent the egg-enriched crust from burning before the interior sets. Many artisan bakers start covered at high heat and uncover partway through.

Most cakes bake at 325–375°F (163–190°C, Gas Mark 3–5). Delicate sponge cakes and chiffon cakes: 325°F. Standard layer cakes and sheet cakes: 350°F. Quick-baking cupcakes: 375°F. Lower temperatures produce more even rise with less doming; higher temperatures produce faster browning and more crust. Cheesecakes are the exception — they bake at a very low 300–325°F in a water bath to prevent cracking.

400–425°F (204–218°C) is ideal for most roasted vegetables. This high heat promotes caramelization and browning through the Maillard reaction, creating complex, sweet flavors. Root vegetables (carrots, potatoes, parsnips) take 30–45 minutes; smaller, softer vegetables (asparagus, zucchini, cherry tomatoes) take 15–25 minutes. Toss in oil and spread in a single layer — crowding the pan causes steaming rather than roasting.

Slow oven cooking for braises and tough cuts uses 275–325°F (135–163°C, Gas Mark 1–3). At these temperatures, collagen in tough cuts like chuck roast and pork shoulder slowly converts to gelatin over 3–5 hours, creating tender, rich meat without drying it out. This temperature range also works for making confit (duck legs, garlic), slow-dried tomatoes, and low-temperature custards.