Percentage Change Calculator
Calculate percentage increase or decrease between two values, with the reverse figure that shows why a 50% drop needs a 100% rise to recover.
Why percentages are not symmetric
A stock that falls 50% must rise 100% to get back to where it started. A price cut of 20% followed by a rise of 20% leaves you 4% below the original. This asymmetry catches people out constantly in investing, retail pricing and performance reporting — the base changes, so the same percentage means a different amount in each direction.
Percentage points versus percent
If an interest rate moves from 4% to 6%, that is a rise of two percentage points and a 50% increase. Both statements are true and they sound wildly different, which is exactly why the distinction gets abused in headlines. Use percentage points whenever the underlying quantity is itself a percentage.
The formula
% change = (new − old) ÷ |old| × 100
Every result on this page comes from this formula. Nothing is rounded until the final display, so figures match a spreadsheet to the cent.
How to use the Percentage Change Calculator
- Fill in each field with your own figures — the defaults are only there as an example.
- The result updates as you type, so there is no button to press.
- Check the breakdown under the main result for the supporting numbers.
- Use the copy button to take the result with you, or share the link to reload the same inputs.
Percentage Change Calculator — frequently asked questions
Is this percentage change calculator free to use?
Yes. Every calculator on the site is free, needs no sign-up, and runs entirely in your browser, so your figures never leave your device.
How accurate is the result?
The maths is exact for the formula shown on the page. Accuracy in the real world depends on your inputs and on assumptions the formula cannot see, so treat the output as a well-grounded estimate rather than a quote.
Can I use it on my phone?
Yes. The page is responsive, weighs a few kilobytes and works offline once loaded, so it behaves the same on a phone as on a desktop.
What people search for
This page answers each of these searches. They are the exact phrases visitors use to find the percentage change calculator.
- percentage change calculator
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About this calculator
Written and reviewed by The Samsung Calculator editorial team. Every calculator is written against a published formula, reviewed against at least one independent reference implementation, and dated when it changes.
Last reviewed August 15, 2026 · Calculation runs client-side · No data collected · Report an error