Loading page
About this tool
Find the percentage increase or decrease between two numbers.
The Percentage Change Calculator finds the percentage change between two numbers using ((new value − original value) ÷ original value) × 100, and labels the result an increase, a decrease or no change. Alongside the percentage it reports the absolute change and the ratio of new to original, rounded to two decimals. Useful whenever you need to say how much something moved rather than just what it moved to.
Open Percentage Change Calculator on AltFTool — it loads instantly in your browser.
Enter the values you already know.
Fine-tune the options to match your scenario.
Read the result and use it in your planning or reporting.
The result is labelled Increase, Decrease or No Change, so a signed number is never misread.
You get the raw difference, the percentage and the new/original ratio from one pair of inputs.
The denominator uses the absolute value of the original, so a negative starting figure still yields a sensibly signed percentage.
Subtract the original from the new value, divide by the original, then multiply by 100. From 80 to 100 that is (100 − 80) ÷ 80 × 100 = +25.00%, which is what this calculator returns.
Because percentage change divides by the original value, and division by zero is undefined — there is no meaningful percentage rise from nothing. The calculator shows a dash and a prompt instead of a number when you enter 0 as the original.
No. Percentage change is directional and measured against the original value, so 80 to 100 is +25%. Percentage difference is symmetric and divides by the average of the two numbers, giving 22.22% for the same pair. This tool computes percentage change.
Divide the new value by (1 + change ÷ 100). If a price is 19,800 after a 10% rise, the original was 19,800 ÷ 1.10 = 18,000. You can confirm it by entering 18,000 and 19,800 here and checking the result reads +10.00%.
Add the Percentage Change Calculator widget to your blog or website — free, responsive, no signup. Just keep the “Widget by AltFTool” credit link visible.
<iframe src="https://www.altftool.com/embed/widget/percentage-change-calculator"
title="Percentage Change Calculator — free AltFTool widget"
width="100%" height="640" style="border:0;border-radius:12px;overflow:hidden"
loading="lazy" referrerpolicy="no-referrer-when-downgrade" allow="clipboard-write"></iframe>
<p style="font-size:12px;margin:4px 0 0">Widget by <a href="https://www.altftool.com/tools/all/percentage-change-calculator?utm_source=embed&utm_medium=widget" rel="nofollow">AltFTool — free online tools</a></p>