ABV Calculator

Introduction

The ABV Calculator helps you figure out the alcohol by volume in your homemade beer, wine, cider, or other fermented drinks. ABV tells you what percentage of your drink is alcohol. To find this number, you need two simple measurements: the original gravity (before fermentation) and the final gravity (after fermentation). Just plug in your readings, and this tool does the math for you in seconds. Whether you are a beginner homebrewer or an experienced drink maker, knowing your ABV is important for tracking your batches and making sure your beverages turn out the way you want them to.

How to Use Our ABV Calculator

Enter your original gravity and final gravity readings to calculate the alcohol by volume (ABV) of your beer, wine, or other homemade beverage.

Original Gravity (OG): This is the gravity reading you take before fermentation begins. It measures how much sugar is in your liquid. A typical beer OG falls between 1.030 and 1.070. You can find this number using a hydrometer or refractometer.

Final Gravity (FG): This is the gravity reading you take after fermentation is done. It tells you how much sugar is left in your drink. A typical beer FG falls between 1.005 and 1.015. Take this reading once your beverage has stopped bubbling and the gravity stays the same for two to three days in a row.

What is ABV?

ABV stands for Alcohol By Volume. It tells you what percentage of a drink is pure alcohol. For example, if a beer has 5% ABV, that means 5% of the liquid in that bottle is alcohol. You'll find ABV listed on the label of almost every alcoholic beverage, from beer and wine to spirits and cocktails.

How is ABV Calculated?

ABV is figured out by measuring the gravity of a liquid before and after fermentation. Before yeast is added, the liquid has a lot of sugar in it. This is called the Original Gravity (OG). After the yeast eats the sugar and turns it into alcohol, the liquid becomes lighter. This is called the Final Gravity (FG). The difference between these two numbers tells you how much alcohol was created.

The basic formula most homebrewers and beverage makers use is:

ABV = (OG − FG) × 131.25

Why Does ABV Matter?

Knowing the ABV of a drink is important for several reasons:

• Responsible drinking: ABV helps you understand how strong a drink is so you can make smart choices about how much to consume.
• Homebrewing: If you brew your own beer, wine, cider, or mead, calculating ABV lets you track how well your fermentation went.
• Flavor and body: Higher ABV often means a fuller, warmer taste. Lower ABV drinks tend to be lighter and more refreshing.
• Legal requirements: Beverage producers are required by law to display ABV on their labels in most countries.
• Calorie awareness: Higher ABV means more calories from alcohol. If you're tracking your nutrition, you can pair your ABV results with a Calorie Calculator or Macro Calculator to keep your diet on track.

Typical ABV Ranges for Common Beverages

• Light beer: 3%–4% ABV
• Regular beer: 4%–6% ABV
• Craft beer: 5%–12% ABV
• Wine: 11%–15% ABV
• Spirits (vodka, whiskey, rum): 35%–50% ABV

Use the calculator above to quickly find the ABV of your homebrew or any fermented beverage. Just enter your original gravity and final gravity readings, and the tool does the math for you. If you're planning a party or event, our Drink Calculator can help you estimate how much to serve, and the Wedding Alcohol Calculator is perfect for figuring out quantities for larger celebrations. Brewing your own pizza to go with your homebrew? Try our Pizza Dough Calculator for the perfect crust every time.

Frequently Asked Questions

What is the difference between Original Gravity and Final Gravity?

Original Gravity (OG) is the measurement you take before fermentation starts. It shows how much sugar is dissolved in your liquid. Final Gravity (FG) is the measurement you take after fermentation is done. It shows how much sugar is left. The yeast eats the sugar and turns it into alcohol, so the FG is always lower than the OG. The bigger the gap between OG and FG, the more alcohol your drink has.

What is the difference between Specific Gravity and Plato?

Specific Gravity (SG) and Plato (°P) are two different ways to measure the sugar content in a liquid. SG compares the density of your liquid to pure water, which has an SG of 1.000. Plato measures the sugar content as a percentage by weight. For example, an OG of 1.050 SG is about 12.4°P. Both give you the same information, just in different units. This calculator lets you use either one.

What is a hydrometer and how do I use it to get my gravity readings?

A hydrometer is a glass tool that floats in liquid. It measures how dense the liquid is. You place it in a sample of your beer or wine, and it sinks to a certain level. You read the number where the liquid surface meets the scale on the hydrometer. Denser liquid (more sugar) makes it float higher. Less dense liquid (less sugar, more alcohol) makes it sink lower. Take one reading before fermentation for your OG and another after fermentation for your FG.

What is the refractometer correction and when should I use it?

A refractometer measures sugar by bending light through a liquid sample. It works great for OG readings, but after fermentation, the alcohol in your drink throws off the reading. The refractometer correction checkbox in this calculator fixes that problem. It uses Sean Terrill's formula to convert your inaccurate refractometer FG reading into a true FG. Only check this box if you used a refractometer for your FG reading. If you used a hydrometer for FG, leave it unchecked.

What is the Wort Correction Factor?

The Wort Correction Factor (WCF) adjusts refractometer readings because most refractometers are calibrated for pure sugar (sucrose) solutions. Beer wort contains other sugars and compounds that bend light differently. The standard WCF is 1.04, which works well for most brewers. If you have calibrated your specific refractometer against a hydrometer, you can enter your own custom value for better accuracy.

Should I use the Standard or Alternate ABV formula?

For most beers and fermented drinks under about 7% ABV, the Standard formula works great. It is simple and accurate enough for everyday brewing. The Alternate formula (Dr. Michael Hall's method) is better for strong beers like imperial stouts, barleywines, and Belgian tripels that are above 7% ABV. At higher gravities, the Standard formula becomes less accurate, and the Alternate formula accounts for that. The calculator shows both results side by side so you can compare.

What is Apparent Attenuation vs Real Attenuation?

Apparent Attenuation measures how much the gravity dropped from OG to FG. It makes it look like the yeast ate more sugar than it actually did because alcohol is lighter than water, which lowers the gravity reading. Real Attenuation corrects for this by calculating the Real Extract, which accounts for the alcohol's effect on density. Real Attenuation gives you a truer picture of how much sugar the yeast actually consumed. Most beers have an apparent attenuation of 72%–82%.

What is Real Extract?

Real Extract is the actual amount of unfermented sugar and other dissolved solids left in your drink after fermentation, measured in degrees Plato. It is different from the Final Gravity reading because FG is affected by the presence of alcohol, which is lighter than water. Real Extract removes that distortion and gives you the true residual sugar content. This number is used to calculate accurate calorie estimates.

How does the calculator estimate calories in my drink?

The calculator offers two methods. The Gravity (ASBC) method uses Real Extract and alcohol by weight to calculate calories from both alcohol and residual carbohydrates. This is more accurate. The ABV (Simplified) method estimates calories mainly from the alcohol content with a simpler carb estimate. Alcohol has about 7 calories per gram, and carbohydrates have about 4 calories per gram. Both methods give you a total per serving plus a breakdown.

What is ABW and how is it different from ABV?

ABW stands for Alcohol By Weight. ABV measures alcohol as a percentage of the total volume of the drink. ABW measures alcohol as a percentage of the total weight. Because alcohol is lighter than water, ABW is always a smaller number than ABV. The conversion is ABW = ABV × 0.79336. For example, a 5% ABV beer is about 3.97% ABW. Some countries use ABW on labels instead of ABV.

Why is my FG higher than my OG?

Your FG should never be higher than your OG. If the calculator shows this error, double check your readings. Common reasons include mixing up the two numbers, taking your FG reading at a very different temperature than your OG, or entering the values in the wrong fields. Make sure you enter the before fermentation reading as OG and the after fermentation reading as FG.

How do I know when fermentation is done so I can take my FG reading?

Fermentation is done when the gravity stays the same for two to three days in a row. Take a gravity reading, wait a day or two, then take another. If the numbers match, fermentation is complete and you can use that as your Final Gravity. Do not rely only on bubbles in the airlock stopping, because CO2 can still escape even after fermentation is finished.

Can I use this calculator for wine, cider, or mead?

Yes. This ABV calculator works for any fermented beverage, including wine, cider, mead, hard seltzer, and sake. The formulas are the same regardless of what you are fermenting. Just enter your OG and FG readings. Keep in mind that wine and mead often have higher original gravities than beer, so the Alternate (High Gravity) formula may give you more accurate results for those drinks.

Does temperature affect my gravity readings?

Yes. Hydrometers are calibrated to read correctly at a specific temperature, usually 60°F (15.6°C) or 68°F (20°C). If your sample is warmer or cooler than that, the reading will be slightly off. Warmer liquid is less dense, so the hydrometer reads lower than the true gravity. Many brewers use a temperature correction chart or calculator to adjust their readings. For the most accurate results, try to take readings at the calibration temperature listed on your hydrometer.

What does the beer style reference table show?

The beer style reference table lists common beer styles with their typical ABV, OG, and FG ranges. After you calculate your ABV, the table highlights any styles that match your result. This helps you see what category your homebrew falls into or compare it to well-known styles like IPAs, stouts, or pilsners.