Tare weight (皮重) is the empty weight of a container—the weight of the carboy or keg when it's completely empty with no liquid inside. Knowing this allows you to subtract it from the total (gross) weight to determine the net weight of the contents.

Knowing the exact tare weight lets you calculate how much beer, wort, or other liquid is inside without having to transfer it to a graduated vessel. Simply weigh the full container, subtract the tare weight, and you have the net weight of your liquid—useful for tracking fermentation progress, bottling day calculations, and inventory management.

The preset values represent typical weights based on common manufacturers, but individual containers can vary by 0.5–2 lbs due to manufacturing tolerances, glass thickness variations, or different models. We strongly recommend weighing your own empty containers and logging them in "My Containers" for maximum accuracy.

Use a reliable digital scale. Make sure the container is completely empty, clean, and dry. Remove all lids, airlocks, gaskets, or accessories unless you plan to include them during regular use. Weigh the container 2–3 times and take the average. Record this value in "My Containers" for future reference.

Ball Lock kegs (originally Pepsi) have round posts with small ball bearings for connections and are slightly shorter and wider. Pin Lock kegs (originally Coca-Cola) have pins on the posts and are taller and narrower. Pin Lock kegs typically weigh about 0.5 lbs more. Both are popular among homebrewers, but Ball Lock is more common in homebrew setups today.

Absolutely! The "My Containers" section lets you add any container type with a custom name, capacity, material, and tare weight. Use it for fermenters, buckets, growlers, bottles, or any vessel you regularly weigh during your brewing process.

Volume is estimated using the formula: Volume = Net Weight ÷ (Specific Gravity × Unit Factor). For water (SG=1.000), 1 gallon ≈ 8.34 lbs and 1 liter ≈ 1 kg. For wort with SG=1.050, 1 gallon ≈ 8.76 lbs. The calculator uses your entered specific gravity to provide a volume estimate alongside the net weight.

Your custom containers and calculation history are saved in your browser's localStorage. This means they persist across sessions on the same device and browser. However, clearing your browser data or using a different browser will lose this data. Use the Export button to back up your container list as a JSON file.

The tool supports pounds (lbs) and kilograms (kg) for weight, and gallons (gal) and liters (L) for volume. You can toggle the display unit in the Preset Library, and the Calculator accepts input in either unit with automatic conversion.