All tools · Utilities

Percentage

Percent of a number, what-percent, and percentage change.

Free to use, no sign-up required. Percentage is one of 198 tools built into Xenition, alongside a chat that can use them for you.

Answers the three everyday percentage questions: what is X% of a number, what percent one number is of another, and the percentage change from an old value to a new one.

How to use Percentage

1. Pick a mode: % of, is what %, or % change.
2. In % of, enter the percent in the first box and the number in the second.
3. In is what %, enter the part first and the whole second. In % change, enter the old value first and the new value second.
4. Read the answer under the line that restates your question.

How it works

X% of Y = X ÷ 100 × Y. A is what % of B = A ÷ B × 100. Percentage change = (new − old) ÷ |old| × 100, so a fall shows as a negative percentage. Results show up to two decimal places.

Example

15% of 240 is 36. 45 is 25% of 180. Going from 80 to 100 is a 25% increase, while going from 100 back to 80 is a −20% change.

Questions about Percentage

Why is a 25% rise followed by a 20% fall back to the same number?

Each percentage is measured against its own starting value. The rise is 20 out of 80, the fall is 20 out of 100, so the same 20-unit gap gives different percentages.

Why is percentage change blank when the old value is 0?

Change is divided by the old value, and dividing by zero has no answer. Growth from nothing cannot be expressed as a percentage.

What it takes

• Percent — The percentage to take
• Value — The base value

Use it from chat

You do not have to open Percentage to use it. Ask Xenition in plain language and it runs the right tool, then carries the answer into whatever you are working on — a document, a spreadsheet, a deck.

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