Percentage Difference Calculator
Calculate the percentage difference, increase or decrease between two numbers. Shows formula and steps. Free.
How to use the % Difference
Three measures explained
% change = (new − old) ÷ old × 100. Use when one value is "before" and the other "after". % difference = |a − b| ÷ ((a+b)/2) × 100. Symmetric — works when neither value is the reference. % of = (a ÷ b) × 100. What proportion one number is of another.
Example: salary rise
If your salary went from £30,000 to £33,000, that's a 10% increase: (33000 − 30000) ÷ 30000 × 100 = 10%. The percentage difference (symmetric) would be different: |33000 − 30000| ÷ 31500 × 100 = 9.52%.
Frequently asked questions
Is the % Difference free to use?
Yes, the % Difference is completely free. There is no sign-up, no account required, and no limit on how often you can use it.
How accurate is the % Difference?
The % Difference uses standard mathematical formulas and produces results accurate to standard precision. For critical applications, always verify with an authoritative source.
What devices does the % Difference work on?
The % Difference works on any device with a modern web browser — desktop, laptop, tablet, or phone. It is mobile-friendly and works offline once the page has loaded.