Calculator Inputs
Results appear above this form after submission.
Example Data Table
Example values illustrate logging, trending, and comparison only.
| Visit | Viral Load (IU/mL) | log10 Viral Load | Change vs Prior (log10) |
|---|---|---|---|
| Baseline | 1,250,000.00 | 6.097 | — |
| Week 4 | 42,200.00 | 4.625 | -1.472 |
| Week 8 | 1,200.00 | 3.079 | -1.546 |
| Week 12 | 28.00 | 1.447 | -1.632 |
Formula Used
log10 viral load = log10(IU/mL)
log10 change = current log10 − previous log10
log10 reduction = previous log10 − current log10
percent change = ((current − previous) ÷ previous) × 100
fold change = current ÷ previous
log10 above lower limit = current log10 − lower limit log10
This page converts entered HCV viral load values into base ten logarithms, compares current and previous samples, and measures distance from an entered quantifiable threshold.
How to Use This Calculator
- Enter a sample label and date.
- Type the current viral load in IU/mL.
- Optionally add previous and target values.
- Set the lower quantifiable limit used by your assay.
- Choose decimal precision for displayed values.
- Click Calculate to see logs, deltas, status, table output, and charted comparison.
FAQs
1. What does log10 viral load mean?
It is the base ten logarithm of the entered viral load. Logs compress very large numbers and make sample-to-sample changes easier to compare visually.
2. Why use IU/mL before converting?
Most laboratory reports present HCV viral load in IU/mL. This calculator expects that unit first, then converts it into a log10 value for comparison.
3. What is log10 change?
Log10 change is the difference between the current and previous log values. Positive values mean an increase. Negative values mean a decrease.
4. What is log10 reduction?
Log10 reduction reverses the subtraction order. It shows how much the current value dropped compared with the previous value. Larger positive reductions indicate stronger declines.
5. Why enter the lower quantifiable limit?
Different assays use different quantifiable thresholds. Adding that limit helps compare the current sample against the entered laboratory reporting boundary.
6. Does this calculator give treatment advice?
No. It performs mathematical conversions and comparisons only. Interpretation should follow laboratory guidance, clinician review, and the specific assay documentation.
7. What does progress toward target show?
When previous and target values are both entered, the calculator estimates how far the current sample moved from the previous value toward the target.
8. What do the CSV and PDF exports include?
The CSV export downloads the results table. The PDF export captures the visible results section, including summary text, table values, and the chart.