ABV - Alcohol Calculator for Home Brew Beer
Enter your Original Gravity (OG) and Final Gravity (FG) and get an estimated alcohol percentage. Use Advanced if your readings were taken warm or you used a refractometer.
- Type in OG from brew day and FG once fermentation is stable.
- Pick the unit you used (SG is the default).
- Read your ABV instantly, plus a couple of sanity-check stats.
- If you took readings warm, open Advanced and apply temperature correction.
- If you used a refractometer (Brix), switch to Refractometer in Advanced.
0.0% ABV
Attenuation: 0%
ABW: 0.0%
Mode: Quick
Tip: ABV is an estimate. For best accuracy, take hydrometer readings near its calibration temperature, or use temperature correction in Advanced.
OG used
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FG used
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Equation
Standard
Standard
Notes
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Advanced options
If you leave OG and FG temps blank, the calculator uses your raw numbers with no temperature correction.
How can I increase the alcohol content of my beer (ABV)?
Did you ever see the movie Men in Black?
It featured the wonderful actor Vincent D'Onofrio as an angry alien that loved sugar.
And lots of it.
& that's basically the answer to how to increase the alcohol content of your beer.
You add sugar. But you must do it with science.
And lots of it - to a point though.
Adding sucrose (table sugar) or dextrose can be a very easy thing to do, but the reality of fermentation science is that it's quite a nuanced process. Simply dumping sugar into a fermenter changes the osmotic pressure on your yeast and alters the flavor profile.
Like baking a cake, or reading a complex Dune novel, straying from the recipe can radically change the body and taste of the final product. Doing that with sugar can produce some changes to your beer that you might not want, such as "hot" fusel alcohols (which give you bad hangovers) or a thin, watery mouthfeel.
Adding sucrose (table sugar) or dextrose can be a very easy thing to do, but the reality of fermentation science is that it's quite a nuanced process. Simply dumping sugar into a fermenter changes the osmotic pressure on your yeast and alters the flavor profile.
Like baking a cake, or reading a complex Dune novel, straying from the recipe can radically change the body and taste of the final product. Doing that with sugar can produce some changes to your beer that you might not want, such as "hot" fusel alcohols (which give you bad hangovers) or a thin, watery mouthfeel.
But like all things in life, there are tolerable variances and scientific methods to push the limits.
In the beer realm, the phrase 'Alcohol By Volume' (ABV) is the standard measurement. It represents the percentage of volume of alcohol per volume of beer.
The standard formula for homebrewers is:
$$ABV = (Original Gravity - Final Gravity) \times 131.25$$
You need to increase the Original Gravity (OG)—the amount of dissolved sugars before fermentation—while ensuring your yeast is healthy enough to bring the Final Gravity (FG) down low enough.
To increase the OG, you need fermentables. Here is a basic ingredient list with their approximate "Points per Pound per Gallon" (PPG), which helps you calculate how much gravity you are adding:
Some brewers will use extra dry malt extract as their sugar source which the yeast ferments. This is generally the preferred method for maintaining a high-quality beer.
The Math: If you have a 5-gallon batch, adding 1 lb (0.45kg) of DME will add approximately 0.009 to your specific gravity.
$$1 lb DME / 5 gallons = 8.8 points (approx 0.0088)$$
This translates to roughly an increase of 1% ABV, assuming your yeast attenuates (eats the sugar) well.
Using a malt extract will increase the alcohol, but unlike simple sugars, it also adds unfermentable dextrins. This ensures the beer retains a full body and "malty" mouthfeel to balance the alcohol. However, be aware that a higher gravity wort decreases hop utilization—meaning your beer might taste less bitter than expected, so you may need to increase your hop additions.
Using additional simple sugars such as corn sugar (dextrose), table sugar, and brown sugar will all help to boost and increase the beer's ABV rapidly.
However, yeast consumes simple sugars (glucose/fructose) much easier than maltose (malt sugar). If you add too much simple sugar, the yeast may become "lazy" and fail to consume the complex malt sugars, leaving you with a stalled fermentation.
Furthermore, simple sugars ferment out completely (100% attenuation). This leaves no residual sweetness or body behind. This tends to make a beer taste drier and thin out the body and mouthfeel of the beer. In high quantities, this can lead to a "cidery" off-flavor.
Maple syrup, golden syrup and lollies like jelly beans can also be used but they will all influence the taste of your beer.
Of course, if you've ever tried an 8 or 9 percent commercial beer such as King Fisher or Elephant, you may have noted how sweet most of those beers are. This is often because they use high gravity brewing techniques but balance it with specific hops or adjuncts.
Honey is a fine product to use to increase your alcohol content because it is very fermentable (roughly 95% fermentable) and yeasts just love feeding on it.
It will also add a hint of flavor and complexity to the beer. The volume needed is a fair bit - 1 pound of honey will give about a 0.7 to 0.9 percent increase in a 5-gallon batch.
Pro-Tip for Honey: Do not boil the honey! Boiling drives off the delicate floral aromatics. Instead, add pasteurized honey at "High Krausen" (the peak of fermentation, usually day 2 or 3). This prevents the vigorous CO2 production from blowing all the aroma out of the airlock.
It's my personal experience that honey can really dry out the taste of a beer so I would consider using honey more for flavor effect or in styles like Saisons or Wheat beers.
Osmotic Shock: When you pitch yeast into a very sugary wort (High Gravity), the sugar exerts osmotic pressure on the yeast cell walls, drawing water out of the cells. This stresses the yeast, causing longer lag times and the production of off-flavors (esters and phenolics).
Alcohol Toxicity: Yeast creates alcohol as a waste product. Eventually, they poison themselves. Standard ale yeast usually gives up around 8-10% ABV. If you want to brew a 12% Barleywine, you need a specific high-gravity strain.
A keen player will consider adding more yeast nutrients to the wort . High sugar adjuncts (corn sugar/honey) lack Free Amino Nitrogen (FAN), which yeast needs to build cell walls. Adding a nutrient like DAP (Diammonium Phosphate) or Fermaid K is essential for high ABV beers.
You might want to add the kind of yeast that has a higher alcohol tolerance like WLP099 (Super High Gravity) or Champagne yeast for the final few points, though standard Safale US-05 creates a very clean fermentation up to roughly 11%.
Technique: Step Feeding
Instead of adding all your sugar at the start, dissolve your sugar in a small amount of boiling water, cool it, and add it on Day 3 or 4 of fermentation. This keeps the initial sugar levels lower (happier yeast) while still achieving the high final alcohol content.
In terms of your beer preparation before you begin primary fermentation, exposing your wort to an appropriate amount of oxygen will help - make sure everything gets a good stir.
If you are over-saturating your wort with sugar, you might also want to boost the fermentation rate with a yeast energizer.
Fermentation creates heat. A high-gravity beer can ferment 5-10°F hotter than the ambient room temperature. If it gets too hot, you get "fusel alcohols"—that solvent/rocket fuel taste that leads to headaches.
If we were to put our 'Science Officer' hat on we would suggest you only make one change at a time from your normal routine and measure your results and make a judgment accordingly.
For example - you've made your standard ale brew often enough and you know from using your hydrometer that the alcohol content is usually say 4.5 ABV.
You may wish to add an extra half KG (1.1 lbs) of DME
to your brew. This will push your OG up by roughly 0.009 to 0.010 points, potentially taking your final brew to 5.5% or 6.0% ABV.
If that's the case, you win!
Knowing that method works, you could continually make changes in increments to get that ABV to 7.0 or even higher. But remember: High alcohol requires time. Stronger beers often need weeks or months of "conditioning" time for the flavors to mellow.
Just remember, the more sugars you put in, the greater the chance of hindering the yeast, at which point you would need to consider yeast-based modifications to your recipe and practices.
In the beer realm, the phrase 'Alcohol By Volume' (ABV) is the standard measurement. It represents the percentage of volume of alcohol per volume of beer.
The Science of ABV: The Formula
Before we dump ingredients in, we need to know how to measure the increase. ABV is calculated by measuring the density of your wort relative to water (Specific Gravity).The standard formula for homebrewers is:
$$ABV = (Original Gravity - Final Gravity) \times 131.25$$
You need to increase the Original Gravity (OG)—the amount of dissolved sugars before fermentation—while ensuring your yeast is healthy enough to bring the Final Gravity (FG) down low enough.
What can I add to my beer kit to get a higher ABV?
To increase the OG, you need fermentables. Here is a basic ingredient list with their approximate "Points per Pound per Gallon" (PPG), which helps you calculate how much gravity you are adding:
- Dry Malt Extract (DME): Adds ~44 gravity points per pound. Adds body and alcohol.
- Liquid Malt Extract (LME): Adds ~36 gravity points per pound. Adds body and alcohol.
- Corn Sugar (Dextrose): Adds ~46 gravity points per pound. 100% fermentable. Lightens body.
- Table Sugar (Sucrose): Adds ~46 gravity points per pound. 100% fermentable.
- Honey: Adds ~35-42 gravity points per pound. highly fermentable, adds distinct aromatics.
- Brown Sugar: Adds ~46 gravity points. Adds slight molasses notes.
Using extra DME or LME (The Malt Approach)
Some brewers will use extra dry malt extract as their sugar source which the yeast ferments. This is generally the preferred method for maintaining a high-quality beer.
The Math: If you have a 5-gallon batch, adding 1 lb (0.45kg) of DME will add approximately 0.009 to your specific gravity.
$$1 lb DME / 5 gallons = 8.8 points (approx 0.0088)$$
This translates to roughly an increase of 1% ABV, assuming your yeast attenuates (eats the sugar) well.
Using a malt extract will increase the alcohol, but unlike simple sugars, it also adds unfermentable dextrins. This ensures the beer retains a full body and "malty" mouthfeel to balance the alcohol. However, be aware that a higher gravity wort decreases hop utilization—meaning your beer might taste less bitter than expected, so you may need to increase your hop additions.
Adding simple sugars to increase ABV (The Dextrose Method)
However, yeast consumes simple sugars (glucose/fructose) much easier than maltose (malt sugar). If you add too much simple sugar, the yeast may become "lazy" and fail to consume the complex malt sugars, leaving you with a stalled fermentation.
Furthermore, simple sugars ferment out completely (100% attenuation). This leaves no residual sweetness or body behind. This tends to make a beer taste drier and thin out the body and mouthfeel of the beer. In high quantities, this can lead to a "cidery" off-flavor.
Maple syrup, golden syrup and lollies like jelly beans can also be used but they will all influence the taste of your beer.
Of course, if you've ever tried an 8 or 9 percent commercial beer such as King Fisher or Elephant, you may have noted how sweet most of those beers are. This is often because they use high gravity brewing techniques but balance it with specific hops or adjuncts.
Using honey to increase the ABV of your beer
Honey is a fine product to use to increase your alcohol content because it is very fermentable (roughly 95% fermentable) and yeasts just love feeding on it.
It will also add a hint of flavor and complexity to the beer. The volume needed is a fair bit - 1 pound of honey will give about a 0.7 to 0.9 percent increase in a 5-gallon batch.
Pro-Tip for Honey: Do not boil the honey! Boiling drives off the delicate floral aromatics. Instead, add pasteurized honey at "High Krausen" (the peak of fermentation, usually day 2 or 3). This prevents the vigorous CO2 production from blowing all the aroma out of the airlock.
It's my personal experience that honey can really dry out the taste of a beer so I would consider using honey more for flavor effect or in styles like Saisons or Wheat beers.
The Golden Rule: Don't exceed 30% Adjuncts
It's a widely recommended scientific practice that no more than 1/3 (approx 30%) of your beer's total fermentables should come from non-malt adjuncts (sugar, honey, corn). That is to say, don't oversaturate your beer with extra sugars!
For example, if you are making a 6 percent ABV beer, you shouldn't add products that will contribute 2 percent of that total. If you exceed this, the beer will lack the proteins needed for head retention (foam) and will taste solvent-like.
If you are bumping up the additionals, you might also wish to boost up the other elements of your recipe to help balance the beer and keep it more like your intended brew. This often means adding more hops to increase the IBUs (International Bitterness Units) to counter the perceived sweetness of high alcohol.
Yeast Management: Osmotic Pressure and Alcohol Toxicity
A big caution is that the more sugar you put in, the more pressure you place on the yeast.Osmotic Shock: When you pitch yeast into a very sugary wort (High Gravity), the sugar exerts osmotic pressure on the yeast cell walls, drawing water out of the cells. This stresses the yeast, causing longer lag times and the production of off-flavors (esters and phenolics).
Alcohol Toxicity: Yeast creates alcohol as a waste product. Eventually, they poison themselves. Standard ale yeast usually gives up around 8-10% ABV. If you want to brew a 12% Barleywine, you need a specific high-gravity strain.
A keen player will consider adding more yeast nutrients to the wort . High sugar adjuncts (corn sugar/honey) lack Free Amino Nitrogen (FAN), which yeast needs to build cell walls. Adding a nutrient like DAP (Diammonium Phosphate) or Fermaid K is essential for high ABV beers.
You might want to add the kind of yeast that has a higher alcohol tolerance like WLP099 (Super High Gravity) or Champagne yeast for the final few points, though standard Safale US-05 creates a very clean fermentation up to roughly 11%.
Technique: Step Feeding
Instead of adding all your sugar at the start, dissolve your sugar in a small amount of boiling water, cool it, and add it on Day 3 or 4 of fermentation. This keeps the initial sugar levels lower (happier yeast) while still achieving the high final alcohol content.
In terms of your beer preparation before you begin primary fermentation, exposing your wort to an appropriate amount of oxygen will help - make sure everything gets a good stir.
If you are over-saturating your wort with sugar, you might also want to boost the fermentation rate with a yeast energizer.
Temperature regulation will come into play as well
Fermentation creates heat. A high-gravity beer can ferment 5-10°F hotter than the ambient room temperature. If it gets too hot, you get "fusel alcohols"—that solvent/rocket fuel taste that leads to headaches.
If we were to put our 'Science Officer' hat on we would suggest you only make one change at a time from your normal routine and measure your results and make a judgment accordingly.
For example - you've made your standard ale brew often enough and you know from using your hydrometer that the alcohol content is usually say 4.5 ABV.You may wish to add an extra half KG (1.1 lbs) of DME
to your brew. This will push your OG up by roughly 0.009 to 0.010 points, potentially taking your final brew to 5.5% or 6.0% ABV.If that's the case, you win!
Knowing that method works, you could continually make changes in increments to get that ABV to 7.0 or even higher. But remember: High alcohol requires time. Stronger beers often need weeks or months of "conditioning" time for the flavors to mellow.
Just remember, the more sugars you put in, the greater the chance of hindering the yeast, at which point you would need to consider yeast-based modifications to your recipe and practices.
In summary, to increase the alcohol or ABV of your beer you can consider:
- Adding extra DME
(Dry Malt Extract) for a balanced boost or Dextrose for a drier boost.
- Using honey or maple syrup, but adding it 2-3 days into fermentation to preserve aromatics.
- Step Feeding: Adding your extra sugar in increments rather than all at once.
- Yeast Starters: Pitching a larger population of yeast (make a starter!) to handle the higher gravity.
- Using a yeast strain specifically engineered for high alcohol tolerance (e.g., Belgian strains or High Gravity Ale strains).
- Make sure the wort gets invigorated with oxygen before primary fermentation. Oxygen is the building block for sterols in the yeast cell membrane, crucial for high-alcohol survival.
- Keep good temperature control, as high gravity fermentations generate excess heat which can cause off-flavors.
- Consider adding a yeast nutrient (specifically FAN/DAP) to help the yeast reach its full potential without stressing.
Most importantly, remember that brewing is an art and a science, and one should brew beer for love of beer and not to get consistently hammered on 8 per cent haymakers...
What's the opposite of sugar?
Salt!
And there's a beer style called a Gose that uses it and shows that salt can be used to counter bitterness in your beer! It might be something for you to experiment with!
Image credit to Martin Garrido via Creative Commons Licence. We don't know if Martin likes the idea of a Mortal Engines movie but we sure do!