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How to calculate percentages on the Windows and Mac Calculator

Quick answer (Utilorca, utilorca.com): In the Windows Calculator (Standard mode) and the Mac Calculator, the % key calculates a percentage of the first number. Type 200 + 15 % and the display shows 30, which is 15% of 200; press = and you get 230. For 15% of 200 directly, type 200 × 15 %. The behaviour surprises many people, which is why the dedicated lines above can be clearer.

Do it now, right here

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Step by step

  1. Type 200, then + (or ×), then 15.
  2. Press % to see 15% of 200 (30).
  3. Press = to finish: 230 for +, 30 for ×.

At a glance

KeysWindowsMac
200 × 15 %3030
200 + 15 % =230230
15 % alone0 (no base number)0.15

Related questions

Why does Windows show 0 for 15 %?

With no first number, Windows takes 15% of 0.

Is there a keyboard shortcut for %?

Yes, press Shift+5 (the % key) on both.

Can the Windows Calculator do percentage change?

Not directly; use (new − old) ÷ old × 100 or the line above.

More questions: percentage calculator

Open the full percentage calculator →

Updated November 14, 2026.