Why does 2+2×3 give 8 and not 12?

Calcnest follows the standard order of operations: multiplication and division are done before addition and subtraction. So 2 + 2 × 3 is 2 + 6 = 8. Simple calculators that work strictly left to right show 12 instead.

How does percent work? Is 50+10% equal to 55?

Yes. The percent key works like a desk calculator: 50 + 10% adds 10% of 50 to get 55, 50 − 10% gives 45, and 50 × 10% gives 5 (10% of 50). For "X is what % of Y" or percent change, use the Percent tool.

Can I convert cups to grams?

Yes. In the unit converter's cooking section, pick water, milk, flour, sugar, butter or rice and convert cups, tablespoons or teaspoons to grams. The ingredient matters: 1 US cup of flour is about 125 g, while 1 cup of sugar is about 200 g.

Is my calculation history limited?

No. Every calculator and tool result is saved automatically with no limit. You can pin important entries, add notes, tap to reuse a result, swipe to delete (with undo) and share an entry as text.

Does it work offline?

Yes. All calculations and unit conversions run on your phone, so it works without internet. There is no currency converter.

How do I add the widget or the Quick Settings tile?

Long-press an empty spot on your home screen, tap Widgets and drag Calcnest onto the screen; it shows your last result, the calculator and 2 favorite tools. For the tile, pull down Quick Settings, tap the edit (pencil) button and drag the Calcnest tile into place.

Do I need an account? Where is my data stored?

No account or sign-up is needed. Your history and settings stay on your phone. The app is supported by ads, and ad sound is muted.

Can I change decimal places or turn off key vibration?

Yes. In settings you can choose decimal places and a thousands separator, turn key vibration on or off, and switch between light and dark theme.

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How the calculator percent key works

On a desk calculator, 50 + 10% gives 55 because the 10% is read as "10% of 50" (which is 5), not as 0.1. In general, A + B% = A × (1 + B/100), A − B% = A × (1 − B/100) and A × B% = A × B/100. Once you know this rule you can get sale prices, markups and tax straight from the calculator.

The three things the % key does

A desk calculator uses the number before the % key as the base. So "50 + 10%" means "add 10% of 50 to 50". Some phone calculators instead turn 10% into 0.1 and show 50.1, which is why the same keys give different answers on different apps.

You type	What it means	Result
50 + 10%	50 plus 10% of 50 (5)	55
50 − 10%	50 minus 10% of 50 (5)	45
50 × 10%	10% of 50	5

Three percent formulas you'll actually use

Most everyday percent questions are one of these three.

X% of Y: Y × X ÷ 100. Example: 15% of 80 = 80 × 15 ÷ 100 = 12
X is what percent of Y: X ÷ Y × 100. Example: 12 is 12 ÷ 80 × 100 = 15% of 80
Percent change: (new − old) ÷ old × 100. Example: 80 → 100 is +25%, 100 → 80 is −20%

Two common traps

Adding 10% and then taking 10% off does not get you back where you started. $100 plus 10% is $110, but $110 minus 10% is $99. To remove a 10% tax from a total, divide: $110 ÷ 1.1 = $100.

Stacked discounts don't simply add up. 20% off and then an extra 10% off takes $100 to $80 and then to $72, a total discount of 28%, not 30%.

Percent change depends on the starting value. Going from 80 to 100 is a 25% increase, but going from 100 back to 80 is a 20% decrease, because the base is different.

How Calcnest handles it

Calcnest's percent key works like a desk calculator, so 50 + 10% = 55, 50 − 10% = 45 and 50 × 10% = 5. It also follows the order of operations, so 2 + 2 × 3 = 8.

The Percent tool answers "X% of Y", "X is what % of Y" and percent change directly, and the Discount tool handles an extra discount on top and shows the final price and the amount saved. Every result is saved to history automatically.

Percent math, without second-guessing

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