Rex says
Everyday utility math — the kind you'd otherwise pull up four browser tabs for. I keep it to one clean answer.
Try a scenario
Click to load — tweak from there.Inputs
Result
ABV (standard)
5.78%
ABV (alternate formula)
5.93%
Apparent attenuation
78.6%
Calories per 12 oz (approx)
663
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One click, a permanent link with your numbers baked in.
How to use this
- 1Enter original gravity.
- 2Enter final gravity.
- 3Read your abv (standard) on the right — it updates as you type.
- 4Hit Share to keep the scenario or send it to someone.
About this calculator
Standard and alternate ABV formulas from hydrometer readings, plus apparent attenuation and calories per 12 oz.
Worked example
Using the values the calculator loads with:
Inputs
- Original gravity: 1.056
- Final gravity: 1.012
Results
- ABV (standard): 5.78%
- ABV (alternate formula): 5.93%
- Apparent attenuation: 78.6%
- Calories per 12 oz (approx): 662.99
What each field means
Inputs
- Original gravity
- The original gravity used in the calculation. Starts at 1.056 so you have a working example on load.
- Final gravity
- The final gravity used in the calculation. Starts at 1.012 so you have a working example on load.
Results
- ABV (standard)
- Returned as a percentage and shown as the headline result. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- ABV (alternate formula)
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Apparent attenuation
- Returned as a percentage. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
- Calories per 12 oz (approx)
- Returned as a whole number. It recalculates instantly whenever you change an input, so you can compare scenarios without reloading.
FAQ
How does the abv calculator work?
Standard and alternate ABV formulas from hydrometer readings, plus apparent attenuation and calories per 12 oz. The underlying maths is: ABV ≈ (OG − FG) × 131.25.
What do I need to enter?
2 values: original gravity, and final gravity. Each field starts with a sensible default, so you can change one number at a time and watch the result move.
What does the abv (standard) result mean?
It is returned as a percentage and updates live as you edit the inputs, so you can compare two or three versions of a scenario in a few seconds.
Is this calculator free, and do I need an account?
Yes, it's free, and no account is required. Nothing you type is stored on our servers — the maths runs entirely in your browser.
How accurate is the result?
It applies the standard formula exactly, so the arithmetic is precise. Estimates assume standard, average conditions — local rules, pricing, and materials vary.
Who is this tool for?
It's built for anyone doing everyday planning maths — a quick estimate that would otherwise need four browser tabs and a calculator app.
Accuracy and limitations
- Estimates assume standard, average conditions — local rules, pricing, and materials vary.
- Results are rounded for readability; add a buffer before ordering, booking, or committing.
- Double-check anything with a real cost attached against a local quote.
Related tools
Cite this calculator
Writing about this topic? Grab a citation — every link helps keep these tools free.
RevenueLab. (2026). ABV Calculator. Retrieved from https://www.revenuelab.fyi/toolbox/abv-calculator
<p>Source: <a href="https://www.revenuelab.fyi/toolbox/abv-calculator" target="_blank" rel="noopener">ABV Calculator — RevenueLab</a> (2026).</p>
Source: [ABV Calculator — RevenueLab](https://www.revenuelab.fyi/toolbox/abv-calculator) (2026).