Probiotic CFU Calculator
Add up the daily CFU count from your probiotic servings and see where it sits against typical everyday and higher therapeutic ranges.
How it works
Total daily CFU = CFU per serving × servings per day · (CFU = colony-forming units, the count of live microbes)
Probiotics are dosed in colony-forming units (CFU) — the number of live, viable microbes — usually quoted in billions. Everyday products commonly land in the 1–10 billion CFU/day range, while some studies for specific conditions use 50 billion or more. A higher count is not automatically better: the strain and whether it survives to the gut matter as much as the number, and the label figure should be guaranteed through the expiry date, not just at manufacture.
Worked example
Taking two capsules of a 10 billion CFU probiotic gives 10 × 2 = 20 billion CFU/day, which sits in the higher everyday range. A single 10 billion capsule would put you at the middle of the typical 1–10 billion band.
Frequently asked questions
Is a higher CFU count better?
Not necessarily. Beyond an effective dose for a given strain, more CFU has not been shown to add benefit. Strain identity and viability at expiry often matter more than a big headline number.
What does CFU actually mean?
Colony-forming units estimate how many live microbes can grow and multiply. It is the standard way to count viable probiotic organisms in a dose.
Should the count be guaranteed at expiry?
Yes. Live cultures decline over time, so a trustworthy label states the CFU guaranteed through the end of shelf life, not just at the time of manufacture.
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Educational estimate, not medical advice. Talk to a doctor, pharmacist or registered dietitian before starting or changing any supplement, especially if you are pregnant, nursing, on medication or managing a health condition.