Measure difference, percent change, and growth rate with confidence for any dataset. Flexible baselines and exports make analysis easy on every device today too.
Sample pair calculation using baseline = old value.
| Old (A) | New (B) | Absolute change (B − A) | Relative change (B − A) ÷ A | Percent change |
|---|---|---|---|---|
| 120 | 150 | 30 | 0.25 | 25% |
| 80 | 60 | -20 | -0.25 | -25% |
| -10 | -4 | 6 | -0.6 | -60% |
Note: changing the baseline changes the relative and percent outputs.
Baseline can be old, new, average, or a custom nonzero value.
Use series mode for stepwise trends and first-to-last summaries.
Absolute change is the difference between two values, computed as Δ = B − A. If sales rise from 120 to 150, Δ = 30 units. This number preserves scale, so it is ideal for capacity planning, budgeting, and error tracking where the unit size matters.
Relative change compares Δ to a reference level. Using the old value baseline, r = 30/120 = 0.25. Using the average baseline, r = 30/135 ≈ 0.2222. Different baselines answer different questions: “growth from where we started” versus “change relative to typical level.”
Percent change simply scales r by 100, giving 25% for the 120→150 example with old baseline. Ratio q = B/A gives 150/120 = 1.25, often read as “1.25×”. Percent and ratio are equivalent when A is nonzero, but percent communicates change while ratio communicates multiplicative level.
When the baseline is zero, relative and percent change are undefined, so the calculator returns a dash. For negative values, interpretation depends on context. Moving from −10 to −4 yields Δ = 6, but using old baseline gives r = 6/−10 = −0.6, meaning the value became less negative by 60% of the starting magnitude.
For a sequence such as 100, 108, 90, 99, consecutive steps reveal volatility: +8%, −16.6667%, +10% using old baselines per step. First→Last summarizes net change: 100→99 is Δ = −1 and −1%. Combining both views separates drift from short‑run swings.
Rounding affects presentation, not the underlying math. Use more decimals for small deltas, like sensor drift of 0.003, and fewer decimals for large counts. For reports, export CSV for spreadsheets and PDF for sharing. Always document your chosen baseline and units alongside the results for audits.
Analysts use change metrics to compare energy bills, conversion rates, laboratory readings, and portfolio values. Engineers track absolute deviations from a setpoint, while managers track percent improvements. In quality control, absolute change flags outliers, and relative change normalizes across product sizes or batch volumes.
A large percent change can come from a tiny baseline, so check absolute size before acting. Conversely, a large absolute change may be at scale. Use series mode to validate whether a change is consistent or a one‑off event, and consider constraints when values cross zero.
Absolute change is the direct difference between a new value and an old value: Δ = B − A. It keeps the original units, so it shows the real size of the shift, not just the percentage.
Relative change divides the absolute change by a chosen baseline, such as the old value, new value, or their average. It is unitless and supports fair comparisons across different scales.
Percent change depends on the denominator. Using the old value answers “how much did we grow from the start,” while using the average supports symmetric comparisons. A custom baseline can match a policy target or reference level.
If the baseline equals zero, relative and percent change are undefined because division by zero is not meaningful. The calculator still reports the absolute change so you can see the raw difference.
Paste two or more numbers separated by commas or new lines. Choose First→Last for a net summary, Consecutive for step-by-step changes, or Both to see trend and volatility together.
Negative numbers are valid. The sign of Δ shows direction, while the sign of relative change depends on the baseline. For values that cross zero, interpret percent change cautiously and consider using absolute change as the primary indicator.
They convey similar information when the old value is nonzero. Ratio is B/A (e.g., 1.25×), while percent change is (B−A)/baseline × 100. Ratio emphasizes level; percent emphasizes change.
Accurate change tracking improves decisions across everyday calculations quickly.
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.