How to use the viable count from colonies calculator
Convert colony counts on a plate into colony forming units per millilitre. Enter colonies counted, dilution plated, volume plated in the fields above; the viable count is computed instantly and plotted on the chart so you can see how the answer changes.
Common searches this calculator answers include “CFU per mL”, “colony count calculation”, “viable bacteria count”, “calculate viable count from colonies”, “find viable count”.
Formula
Variables
- colonies — Colonies counted
- dil — Dilution plated
- V — Volume plated (mL)
Worked example
With colonies counted = 45, dilution plated = 0.000001, volume plated = 0.1 mL, the calculator gives viable count ≈ 450,000,000 CFU/mL.
Frequently asked questions
What is the viable count from colonies calculator used for?
Convert colony counts on a plate into colony forming units per millilitre. It helps with questions such as “CFU per mL”, “colony count calculation”, “viable bacteria count”.
What is the formula for the viable count from colonies calculation?
Viable count (CFU/mL) = colonies / (dil × V). Here colonies is colonies counted, dil is dilution plated, V is volume plated (mL).
What inputs do I need for the viable count from colonies calculator?
You need colonies counted, dilution plated, volume plated in mL. Each field is pre-filled with a typical example so you can see how the result responds as you edit the numbers.
How do I use the viable count from colonies calculator?
Type values into the input fields. Results and the chart update instantly. Use Reset to restore the example values, Copy results to paste them elsewhere, or Share to copy a link that preserves your inputs.
Is the viable count from colonies result exact?
Calculations use standard formulas and double-precision arithmetic, then display about seven significant figures. Real-world measurements carry uncertainty, so treat results as estimates unless your inputs are exact.