COD Load Calculator

Turn lab COD readings into daily mass loads. Use flexible flow units and stream summaries. Download clear CSV and PDF reports in seconds now.

Calculator
Enter one or more streams, then calculate total loading.
Outputs are shown in kg/day.
Used only when reporting period is per month.
Applies to the selected period load for design checks.
Controls display precision in the results table.
Streams
Add multiple discharges to compute a combined load.
Stream name Flow Flow unit COD COD unit
Volume per day
Typical lab report unit
Common for metered discharges
Typical lab report unit
Volume per day
Typical lab report unit
Empty rows are ignored. Negative values are rejected.
Reset
Formula used
Conversion is handled automatically by unit selections.

The calculator converts all flows to m³/day and all COD values to mg/L. It then applies the standard mass loading relationship:

COD Load (kg/day) = COD (mg/L) × Flow (m³/day) ÷ 1000
  • mg/L is numerically equal to g/m³.
  • 1 L/s = 86.4 m³/day, 1 MLD = 1000 m³/day.
  • The selected reporting period scales the per‑day load (hour ÷24, month × days, year ×365).
  • Design load applies your safety factor to the selected period value.
How to use this calculator
A practical workflow for site reporting and design checks.
  1. Select a reporting period that matches your report needs.
  2. If using monthly output, enter the number of month days.
  3. Enter each stream flow and choose the correct flow unit.
  4. Enter each stream COD and choose the COD unit from your lab.
  5. Optional: apply a safety factor for conservative design loading.
  6. Press Calculate COD Load to view results above.
  7. Use the CSV or PDF buttons to save your calculation record.
Example data table
Sample inputs with computed loads (illustrative only).
Stream Flow Flow unit COD COD unit Load (kg/day)
Influent 2,500 m³/day 350 mg/L 875.000
Process Drain 18 L/second 900 mg/L 1,399.680
Sanitary 120 m³/day 500 mg/L 60.000
Total 2,334.680
Example check: Process Drain uses 18 L/s × 86.4 = 1,555.2 m³/day, then 900×1,555.2÷1000 = 1,399.68 kg/day.

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Important Note: All the Calculators listed in this site are for educational purpose only and we do not guarentee the accuracy of results. Please do consult with other sources as well.