How to use it
- Enter the old value.
- Enter the new value.
- Click Calculate to see the change percentage.
What it does – The Change Percentage Calculator takes an original number and a new number, then tells you how much the value has grown or shrunk as a percent. This single figure lets you quickly assess performance, price moves, or any metric shift without manual math.
Why it matters – Knowing the percent change helps you compare results across time, set realistic targets, and communicate impact clearly to stakeholders.
How to read the result – A positive percentage means an increase; a negative percentage means a decrease. For example, old value = 100 and new value = 150 yields a 50% increase. If the new value were 80, the calculator shows –20%, indicating a drop. The result is presented with one decimal place, ready to copy into reports.
Pro tips
- Always enter the older figure first; swapping reverses sign.
- Round the displayed result to the nearest whole number for high‑level summaries.
- Use consistent units (dollars, users, units) for both inputs.
- Double‑check that the old value isn’t zero; the tool requires a non‑zero baseline.
Real-life examples
- A small business owner compares last month’s revenue to this month’s to gauge growth.
- A marketer measures click‑through rate change after a campaign tweak.
- An investor tracks a stock’s price movement from the previous close to today.
Case study
Sarah, a freelance designer, entered her monthly earnings: $2,000 last month and $2,600 this month. The calculator returned a 30% increase, giving her a concrete figure to justify a rate raise to clients.