Percentage Calculator

Compare two values, apply percentage increases or decreases with compounding, and reverse-calculate wholes from known parts—all in a single, shareable summary.

Compare two values

Understand relative size, percentage difference, and the absolute gap.

Quick comparison
Comparison results
80 vs 120
66.67%

How large Value A is relative to Value B

Difference
-40

-33.33% relative to Value B

Increase from smaller to larger
50.00%

How much the smaller number grows to reach the larger

Category
Value A is lower

Based on absolute comparison

Apply a percentage

Instantly calculate increases, decreases, and compound growth.

Adjustments

Useful for monthly growth, yearly returns, or repeated discounts.

Adjustment results
Amount change
18

12% of 150

Increase
168

Base plus the rate

Decrease
132

Base minus the rate

3× compounded
210.7392

Repeatedly apply the rate

PeriodValue
1168
2188.16
3210.7392

Reverse lookup

Work out the original whole when you only know a part and its percentage.

Find the whole
Reverse lookup results
Whole value
300

45 is 15% of this

Percentage check
15.00%

Consistency check rounding to two decimals

Remainder
255

What's left after removing the known part

Frequently Asked Questions