How to use the biochemical oxygen demand calculator
Compute BOD from dissolved oxygen readings. Enter initial do, do after 5 days, dilution factor in the fields above; the bod₅ is computed instantly and plotted on the chart so you can see how the answer changes.
Formula
Variables
- do1 — Initial DO (mg/L)
- do2 — DO after 5 days (mg/L)
- df — Dilution factor
Worked example
With initial do = 8.5 mg/L, do after 5 days = 4.2 mg/L, dilution factor = 10, the calculator gives bod₅ ≈ 43 mg/L.
Frequently asked questions
What is the formula for the biochemical oxygen demand calculation?
BOD₅ (mg/L) = (do1-do2) × df. Here do1 is initial do (mg/L), do2 is do after 5 days (mg/L), df is dilution factor.
What inputs do I need for the biochemical oxygen demand calculator?
You need initial do in mg/L, do after 5 days in mg/L, dilution factor. 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 this 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 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.