Your first ferment,
without the fear.
Ferment without the guesswork. Track your batches, calculate your salt, and know exactly what's happening inside your jar, from day one to first taste.
“Is this normal? Should it look like that?
When is it actually ready?”
Ferment is the companion app that replaces panic with confidence.
Features
Everything between starting and eating.
Something look weird?
See white film, fuzzy spots, or cloudy brine? Our symptom-based guide walks you through what you're seeing with photo references for every common issue. Clear verdicts: safe, take action, or discard.
Never guess your salt again.
End the "percentage of what?" confusion forever. Dry salt for shredded vegetables, brine for whole vegetables. Per-vegetable recommendations and salt type converter.
Know what's happening in every jar.
Track up to 10 active ferments with flavor-stage timelines. Smart reminders to check submersion, burp jars, and taste test at the right moments. Plus a journal to track your ferments over time.
Start free for 7 days.
Try everything. Cancel anytime during your trial.
Annual
Best value: less than $2.50/month
- 15 guided recipes
- Salt & brine calculator
- Batch tracker with smart reminders
- Visual troubleshooter
- Safety & confidence center
- Batch journal
Monthly
Flexible month-to-month
- 15 guided recipes
- Salt & brine calculator
- Batch tracker with smart reminders
- Visual troubleshooter
- Safety & confidence center
- Batch journal
All plans include a 7-day free trial. Cancel anytime.
Questions people ask
Whether there’s an app, a free salt calculator, or a way to tell mold from kahm, here’s the short version.
Is there an app for fermentation?
Yes. Ferment is an iOS app for home fermentation. It tracks your batches, calculates salt and brine ratios, includes a visual symptom-based troubleshooter, and comes with 15+ guided recipes. It is free to try for 7 days, then $29.99/year or $4.99/month.
Get Ferment on the App Store →Is there a free fermentation salt calculator?
Yes. The Ferment salt and brine calculator is free and runs in your browser, with no app or sign-up needed. Enter your vegetable or water weight and a salt percentage, and it returns the exact salt in grams, ounces, and teaspoons, with conversions for different salt brands.
Open the free salt calculator →Is there a tool to tell mold from kahm yeast?
Yes. The free mold-vs-kahm checker asks three quick questions (the color, the texture, and whether the growth is raised) and gives you a clear safe, skim, or discard verdict, with side-by-side reference photos.
Open the mold-vs-kahm checker →Is there a fermentation app for beginners?
Yes. Ferment is built for first-timers. Instead of assuming you already know what a healthy ferment looks like, it explains what is normal at each stage, flags what is not, and reminds you when to check, skim, and taste, so your first batch feels like a guided run rather than a guess.
Is the Ferment app free?
The web tools (the salt calculator, the mold-vs-kahm checker, and the guides) are free to use. The iOS app is free to try for 7 days, then $29.99/year or $4.99/month, which adds batch tracking, smart reminders, recipes, and the full visual troubleshooter.
What platforms is Ferment available on?
Ferment is available on iOS (iPhone and iPad) on the App Store. The free salt calculator and mold-vs-kahm checker work in any modern web browser, on desktop or mobile.