CFU Calculator - You can calculate the concentration ofbacteria.

CFU Calculator

Enter the number of colonies and dilution factor and volume of the cultural plate and the tool will find the CFU.

No. of Colonies [nc]:

Dilution Factor [DF]:

Volume of Culture Plate [vc]

m³ ▾

The CFU calculator estimates the total number of bacteria per unit volume or weight. CFU stands for Colony Forming Unit (CFU/ml), which is essential for determining microbial concentration on a culture plate.

What Is CFU Counting?

Bacterial concentration measures the number of colonies per milliliter of culture. The total count of colonies observed on an agar plate is multiplied by the dilution factor to determine the CFU/ml.

CFU/ml Formula:

The CFU/ml can be calculated using the formula:

CFU = (n_c × DF) / V_c

Where:

n_c = Number of colonies observed
DF = Dilution factor
V_c = Volume of culture plate (ml)

This formula helps estimate the concentration of microorganisms, allowing accurate growth of colonies at desired levels.

Example Calculation:

Suppose you count 9 colonies on a plate with a dilution factor of 7 and a plate volume of 10 m³. Calculate CFU:

Number of colonies (n_c) = 9
Dilution Factor (DF) = 7
Volume of culture plate (V_c) = 10 m³

Solution:

CFU = (n_c × DF) / V_c = (9 × 7) / 10 = 63 / 10 = 6.3 CFU/m³

CFU can also be converted to other units, such as CFU per milliliter or per gram, depending on the sample volume or weight.

How the CFU Calculator Works:

Input:

Enter the number of colonies, dilution factor, and volume of the culture plate.
Click "Calculate".

Output:

Colony Forming Unit (CFU)
Detailed CFU measurements

FAQs

How Many Cells Are in 1 CFU?

1 CFU typically represents approximately 1000 viable cells. The CFU calculator provides results in CFU units and helps estimate the number of colonies that can grow on agar plates.

References:

Unacademy: CFU – How to Calculate CFU?
Techni-k: Microbes – CFU Calculation