Calculator Inputs
Enter blank and sample titration volumes, then calculate COD.
Example Data Table
Use this sample dataset to verify formatting and exports.
| Sample ID | Blank (mL) | Trial 1 (mL) | Trial 2 (mL) | Normality | Sample Volume (mL) | Dilution | Average COD (mg/L) |
|---|---|---|---|---|---|---|---|
| WW-101 | 12.50 | 10.10 | 10.05 | 0.1000 | 50.00 | 1.000 | ≈ 384 |
| SW-014 | 12.50 | 12.10 | 12.15 | 0.1000 | 50.00 | 1.000 | ≈ 56 |
| IND-220 | 12.50 | 7.20 | 7.30 | 0.1000 | 25.00 | 5.000 | ≈ 8480 |
Formula Used
This tool uses the standard dichromate titration relationship:
COD (mg/L) = (A − B) × N × 8000 ÷ Vsample × DF
- A = blank titrant volume (mL)
- B = sample titrant volume (mL)
- N = titrant normality (eq/L)
- Vsample = sample volume used (mL)
- DF = dilution factor applied to the sample
- 8000 = conversion factor to mg O₂ per liter
How to Use This Calculator
- Run a blank and record its titrant volume (A).
- Titrate your digested sample and enter trial volumes (B).
- Enter titrant normality (N) and sample volume used.
- If the sample was diluted, set the dilution factor (DF).
- Click Calculate COD to view trial and summary values.
- Use Download CSV or Download PDF for records.