Money · Number engine
Percentage Change Engine
Work out the percentage increase or decrease between two values with a clear result and worked explanation.
Instant result
Plain-English why
Copyable takeaway
What this means
This is an increase because the new value is above the starting value. The gap is 20, and that gap equals 25% of the original number.
Formula used
Percentage change = ((new value - old value) / old value) x 100
Worked example
If the old value is 80 and the new value is 100, the change is 20. Divide 20 by 80, then multiply by 100 to get 25%.
Common questions
Why does a decrease show as negative?
The sign makes the direction explicit, so you can see whether the number went up or down.
Can I use this for money?
Yes for simple comparisons, but not as financial advice or a substitute for fees, tax, or compound growth modelling.
Plain-English summary
That is a clear increase, so the new value is meaningfully higher than the starting one.
This section translates the result into a short, direct takeaway rather than leaving the page at a bare number.
Read the guide
How to calculate percentage change without overthinking it
A plain-English explainer with the formula, a worked example, and when the result can mislead.
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