Kombucha

Brew balanced kombucha, by the numbers.

Start with the brewing master ratio, dial sugar exactly, scale to your jar, then bottle for fizz. Each tool points to the next one.

tools
5
guides
24
always
FREE
Choose a calculator Help me choose
Amber kombucha with fine bubbles served beside a swing-top bottle

The workflow

Use the kombucha flow in four steps

01

Build the master recipe

Set tea, sugar, starter, and water.

02

Dial sugar to taste

Pick a dry, balanced, or sweet profile.

03

Scale to any vessel

Hold ratios steady from 1L to 25L.

04

Bottle for fizz

Set 2F sugar or juice and timing.

05

More calculators

Troubleshoot

Common kombucha problems these tools solve

  • Too vinegary

    Recheck 1F duration and temperature with the brewing calculator.

  • Not fizzy after bottling

    Use the second fermentation calculator to increase sugar or the 2F window.

  • Mold risk

    Confirm starter ratio and acidity before sealing.

  • Inconsistent results

    Use the batch calculator to lock ratios when scaling.

  • Slow SCOBY growth

    Adjust sugar/starter and keep the jar in an active temp zone.

  • Weak flavor after 2F

    Raise juice percentage or extend 2F based on temperature.

Learn

Kombucha guides

After the batch

What to write down after each brew

  1. 1

    Before pitch: batch volume, tea grams, sugar grams, starter %.

  2. 2

    During 1F: temperature, day-by-day taste from day 7, pH spot checks.

  3. 3

    At pull: final pH, sweetness, aroma, SCOBY condition.

  4. 4

    During 2F: flavoring amount, bottle type, room-temp days.

  5. 5

    Next change: tweak one variable only per batch.

FAQ

Common kombucha questions

How much sugar should I use for kombucha?
The standard ratio is 1 cup of sugar per gallon of tea (about 200g per 4 litres). The SCOBY consumes most of this during fermentation, leaving a mildly sweet, tangy brew. Our sugar calculator adjusts for any batch size.
How long does the first fermentation take?
Typically 7–14 days at room temperature (20–25°C / 68–77°F). Taste-test from day 7. The longer it ferments, the more vinegary it becomes.
What ratio of starter liquid to sweet tea should I use?
Use 10–20% starter liquid (finished kombucha) by volume. For a 1-litre batch, that's 100–200ml of starter. This acidifies the brew immediately and prevents mould growth.
How long does second fermentation take?
Second fermentation is usually 2–5 days at room temperature, depending on sugar level, bottle seal quality, and temperature. Warmer rooms carbonate faster.
What temperature is best for brewing kombucha?
Most brewers get the best balance around 22–25°C (72–77°F). Colder slows fermentation and can leave batches too sweet; hotter ferments quickly and can push vinegar notes.
Can I use honey or stevia instead of sugar?
White sugar is the most reliable option for SCOBY health and consistent fermentation. Honey can work in some methods but often changes microbe balance; stevia does not feed fermentation.
Why does my SCOBY sink or float?
Both are normal. SCOBYs can sink, float, or sit sideways as CO2 develops and releases during fermentation. Position alone is not a health signal.
How do I know when kombucha is done?
Taste is the practical signal: move from sweet tea toward balanced tang. Most batches finish in 7–14 days, but temperature and ratio shift timing. Use pH and daily tasting together.
Can I reuse a SCOBY indefinitely?
Yes, if it stays healthy and contamination-free. Trim old layers when thick, keep enough starter liquid, and maintain clean handling practices between batches.

From our shop

Ads.txt