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Sync settings

Choose what your account keeps in step on every device where you are signed in.

  • My tools

    Always synced: the tools on your board, their order and size.

  • The windows open on your start page, including what you typed in them.

  • Every note in the notepad – on the notepad page, on your board and in windows.

  • Every list of website shortcuts – on the shortcuts page, on your board and in windows.

  • Every grid in the cover grid maker – on its page, on your board and in windows.

  • Every list of bookmarked organisations in the OIN lookup – on its page, on your board and in windows.

  • Keeps your pipeline and saved recipes on all your devices. Your files are never synced – only the steps and settings.

Turning something off removes it from your account straight away. Your devices keep their own copy.

Notifications

Tools that can tell you about something new while a Synsi tab is open, even when you are in another tab or app. Choose them for this browser.

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Notifications are blocked for this site. Allow them in your browser’s site settings (the icon left of the address), then switch them on here.

  • Says “New message” while a Synsi tab is open – never who wrote it or what.

Your choice is stored in this browser only. Notifications never show personal content such as a message or a number. They work while a Synsi tab is open; closed tabs get none.

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Percentage Calculator

Work out percentages in seconds: X% of a number, what percentage one number is of another, percentage change, and adding or subtracting a percentage.

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Result

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Runs in your browser – your data never leaves your device Also available via our free API

How to use the Percentage Calculator

  1. 1 Pick the type of calculation, for example “X% of Y” or “% change”.
  2. 2 Enter the two numbers.
  3. 3 Read the result and the explanation underneath.

Five percentage calculations

1. X% of Y – multiply Y by X and divide by 100. 15% of 200 = 200 × 15 / 100 = 30.

2. X is what percent of Y – divide X by Y and multiply by 100. 25 out of 80 = 25 / 80 × 100 = 31.25%.

3. Percentage change – subtract the old value from the new value, divide by the old value and multiply by 100. From 80 to 100: (100 − 80) / 80 × 100 = 25% increase. A negative result means a decrease.

4. Add a percentage – multiply by (1 + X/100). 250 plus 10% = 250 × 1.10 = 275.

5. Subtract a percentage – multiply by (1 − X/100). 80 minus 25% = 80 × 0.75 = 60.

Percentage change vs. percentage points

If an interest rate rises from 2% to 3%, it went up by one percentage point – but by 50 percent relative to where it started. Use the “% change” mode for the relative change.

A common trap: up and down again

Increasing a price by 20% and then decreasing it by 20% does not bring you back to the start: 100 → 120 → 96. The second percentage is taken from a larger number. To undo an increase of X%, divide by (1 + X/100) instead.

Frequently asked questions

How do I calculate a percentage of a number?

Multiply the number by the percentage and divide by 100. For example, 20% of 150 is 150 × 20 / 100 = 30.

How do I calculate percentage increase?

Subtract the original value from the new value, divide by the original value and multiply by 100. Choose “% change” to let the calculator do it.

Can the percentage change be more than 100%?

Yes. If a value more than doubles, the increase is over 100%. Going from 50 to 150 is a 200% increase.

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