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How to Use the CFU Calculator
Sample Types:
- Liquid sample: Results in CFU/mL
- Solid sample: Results in CFU/g (requires sample mass)
Dilution Formats:
- Scientific notation: 10⁻⁴, 1e-4
- Ratio notation: 1:10, 1:100
- Standard: 10^-4
Countable Range:
- Valid: 30-300 colonies (highlighted in green)
- Too few: <30 colonies (yellow warning)
- Too many: >300 colonies (yellow warning)
Formula:
- CFU/mL = (Colonies × Dilution Factor) / Volume Plated (mL)
- Geometric mean used for multiple valid plates
Keyboard Navigation: Tab to navigate, Enter to calculate, Space to toggle.
