Calculate perfect ingredient ratios for your kombucha brew
Most home brewers start with 1-2 gallons
Your Recipe
1 gallons
of delicious kombucha
Water
14 cups
Sugar
1 cups
Tea Bags
8
or 0.5 oz loose
Starter Liquid
2 cups
Use Clean Equipment
Sanitize all equipment with white vinegar. Never use soap - residue can harm your SCOBY.
Temperature Matters
Keep your brew at 75-85°F (24-29°C). Below 70°F slows fermentation and risks mold.
Test Before Bottling
Taste daily after day 5. When it's slightly sweeter than you want, it's ready to bottle.
Inputs
Result
Perfect starter batch. Use 14 cups water, steep 8 tea bags, add 1 cup sugar. Cool to room temp, add SCOBY and starter, cover with cloth, and wait 7-10 days.
Inputs
Result
Large batch for experienced brewers. Use a 5+ gallon glass container, multiple SCOBYs for faster fermentation, and taste daily after day 7.
Inputs
Result
Shorter fermentation keeps more sweetness. Perfect base for fruit flavoring in F2. Great for those new to kombucha or who prefer milder flavors.
Use 1 cup (200g) of sugar per gallon of kombucha. The sugar feeds the SCOBY during fermentation - most is consumed by the culture, leaving only 2-6 grams per serving in the finished brew depending on fermentation time.
White granulated sugar works best because it provides the cleanest fermentation. Raw sugar, honey, or maple syrup can be used but may produce inconsistent results and different flavors. The SCOBY converts sugar into organic acids, CO2, and trace amounts of alcohol.
Use 8 tea bags or 2 tablespoons of loose leaf tea per gallon of water. Black tea works best for beginners due to its high tannin content which the SCOBY loves, though green, white, and oolong teas also work well.
| Tea Type | Tea Bags/Gallon | Flavor Profile | SCOBY Health |
|---|---|---|---|
| Black Tea | 8 | Bold, traditional | Excellent |
| Green Tea | 10 | Light, grassy | Very Good |
| Oolong Tea | 9 | Floral, complex | Very Good |
| White Tea | 10 | Delicate, mild | Good |
Add 1-2 cups of starter tea (mature kombucha) per gallon batch, which is 10-15% of your total volume. This acidifies the brew to pH 4.5 or lower, protecting it from mold and unwanted bacteria during the first days of fermentation.
Starter liquid is just as important as the SCOBY. It contains the acidic environment and beneficial bacteria needed for a healthy ferment. For your first brew, use the liquid that came with your SCOBY. Never use pasteurized store-bought kombucha as starter.
First fermentation (F1) takes 7-14 days depending on temperature and desired sweetness. At 75-85°F (24-29°C), expect 7-10 days for balanced kombucha. Second fermentation (F2) with flavoring takes 2-4 days in sealed bottles.
| Temperature | F1 Duration | Flavor Result | SCOBY Growth |
|---|---|---|---|
| 65-70°F (18-21°C) | 14-21 days | Mild, sweet | Slow |
| 75-80°F (24-27°C) | 7-10 days | Balanced | Normal |
| 80-85°F (27-29°C) | 5-7 days | Tart, tangy | Fast |
SCOBY stands for Symbiotic Culture of Bacteria and Yeast. It's the "mother" that ferments your tea. Keep it in a glass container with starter liquid, feed it sweet tea every 1-4 weeks, and store at room temperature. A healthy SCOBY is opaque and 1/4 to 1/2 inch thick.
Homemade kombucha typically contains 0.5-2% alcohol by volume (ABV). Longer fermentation, warmer temperatures, and more sugar produce higher alcohol content. Commercial kombucha is regulated to under 0.5% ABV. For lower alcohol, ferment shorter at cooler temperatures.
| Fermentation Style | Estimated ABV | Flavor | Fermentation Time |
|---|---|---|---|
| Sweet (short) | 0.3-0.5% | Sweet, mild | 5-7 days |
| Balanced | 0.5-1.0% | Sweet-tart | 7-10 days |
| Dry (long) | 1.0-2.0% | Tart, vinegary | 10-14 days |
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Last Updated: Feb 12, 2026
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