Kettle Size Calculator

How It Works

Your brew kettle needs to be large enough to hold the pre-boil volume plus headspace for foam and a rolling boil. For a typical 5-gallon batch, you need about 6.5-7 gallons pre-boil, which means an 8-10 gallon kettle is ideal. The 20% headspace rule prevents boil-overs, which are messy and can be dangerous on a stovetop. An oversized kettle is always better than undersized — it gives you room to brew larger batches in the future. Look for kettles with volume markings, a ball valve for easy draining, and a thermometer port. Stainless steel is preferred over aluminum for durability and ease of cleaning.