Dilution Calculator (ABV to ABV)
Enter your current volume and alcohol strength, then choose a lower target ABV. The calculator tells you how much water to add.
Tip: You can use any volume unit as long as you stay consistent. Output uses the same unit.
What is alcohol dilution?
Alcohol dilution is the process of lowering alcohol strength (ABV) by adding water. This is common when working with high-proof spirits, extracts, tinctures, or lab solutions. The key principle is simple: the amount of pure alcohol stays the same after dilution—you only increase total volume.
The core formula
The standard formula is:
- C1 = starting concentration (ABV %)
- V1 = starting volume
- C2 = target concentration (ABV %)
- V2 = final volume after dilution
From this, you can calculate:
- Final volume: V2 = (C1 × V1) / C2
- Water to add: Water = V2 − V1
Example calculation
Scenario
You have 500 mL at 80% ABV and want 40% ABV.
- Pure alcohol = 500 × 0.80 = 400 mL
- Final volume at 40% = 400 / 0.40 = 1000 mL
- Water to add = 1000 − 500 = 500 mL
So you would add 500 mL of water.
When this calculator is useful
- Lowering high-proof neutral spirit to bottling strength
- Preparing infusion bases for liqueurs or bitters
- Adjusting tincture strengths
- Educational chemistry and solution-prep practice
Important practical notes
1) You can only dilute downward
If your target ABV is higher than your starting ABV, adding water cannot achieve it. You would need stronger alcohol, not dilution.
2) Units must match
If you start in liters, your output is in liters. If you start in ounces, output is ounces.
3) Real-world volume behavior
In precise lab or distillation work, alcohol-water mixing can involve slight volume contraction and temperature effects. For everyday use, this calculator gives a practical estimate using the standard formula.
Safety and legal reminders
- Always label containers clearly with ABV and date.
- Use food-safe or lab-safe water, depending on your use case.
- Follow local laws and regulations regarding alcohol handling and production.
- Keep high-proof alcohol away from heat and open flames.
Quick FAQ
Can I dilute to exactly 0% ABV?
No practical finite amount of water gives exactly 0%; ABV approaches zero as volume becomes extremely large.
Can I use this for non-alcohol solutions?
Yes—the same concentration equation works for many dilution problems.
Why does the calculator reject higher target ABV?
Because dilution only decreases concentration. To increase ABV, you must blend with a stronger alcohol source.