How do I weigh a keg?

Use bathroom scales or luggage scales. Weigh the keg when full (after filling), note the empty weight from the keg markings or weigh it empty, then weigh it periodically to track remaining volume.

What does an empty Corny keg weigh?

A standard 19L (5 US gallon) Cornelius ball-lock keg typically weighs 3.5-4.5 kg empty. Pin-lock kegs are slightly heavier at 4-5 kg. Check your specific keg as weights vary.

Why use weight instead of a sight glass?

Weighing is the most accurate non-invasive method. Sight glasses require modification, floating dip tubes can be inaccurate, and tapping the keg to listen for the fill level is unreliable.

Does beer density affect the calculation?

Beer density is approximately 1.01 kg/L for most finished beers, very close to water. High-gravity beers may be slightly denser but the difference is negligible for volume estimation.

How accurate is the weight-based method?

Weight-based keg volume measurement is very accurate (within 0.1-0.2L) if you know the empty keg weight precisely. Weigh your empty keg when you first get it and record it. CO2 weight is negligible. This method works for any keg size.

BrewCalcs

Keg Volume Calculator — Brewing Equipment

Calculate remaining beer volume in a keg by weight.

Full Keg Weight

Weight when just filled

Current Keg Weight

Weight now

Empty Keg Weight

Keg tare weight

Keg Type (reference)

For reference only — calculation uses weights

How We Calculate This

Weight-to-Volume Conversion

Remaining Volume = (Current Weight - Empty Weight) / Beer Density. Beer density is approximately 1.01 kg/L. Subtract the empty keg weight to get the beer weight, then divide by density to get volume in litres.

Tracking Consumption

By knowing the full weight and current weight, you can calculate the percentage remaining and the number of pints left. This helps plan when to brew your next batch or bring a fresh keg to an event.

Frequently Asked Questions

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Last updated: February 2026

All calculations are estimates. Always verify values and adjust based on your equipment and ingredients.