With the percentage calculator, you can work out any percentage problem online in seconds: x per cent of y, the percentage share, the change, a discount or VAT. For every result, it shows you the step-by-step calculation and the formula. Select what you want to calculate in the calculator and type your numbers directly into the equation.
Key points at a glance
- Percentage: Base value × percentage ÷ 100. 20 % of CHF 50 is CHF 10.
- Percentage: Percentage ÷ base value × 100. CHF 15 out of CHF 60 is 25 %.
- Base value: Percentage value × 100 ÷ percentage. If CHF 30 is exactly 15 %, the total is CHF 200.
- Change: (new − old) ÷ old × 100. From 80 to 100, that’s +25 %; going back, it’s −20 %.
- Discount: Price × (1 − discount ÷ 100). A 20 % discount on CHF 149 gives CHF 119.20.
- Calculating the service: Final price ÷ (1 + percentage). For 8.1 % VAT, this is therefore ÷ 1.081, not simply −8.1 %.
Calculating percentages: formulas and examples
Every percentage calculation involves three figures. If you know two of them, you can work out the third.
- Base value: the whole lot, i.e. 100 %.
- Percentage: the percentage.
- Percentage: the proportion in Swiss francs, units or points.
Per cent means «out of a hundred». 20 % is 20 out of 100, which is 0.2 as a decimal. You can do calculations quickest using the decimal form.
Percentage: x % of y
How much is 20 % of CHF 50? The formula is base value × percentage ÷ 100, so 50 × 20 ÷ 100 = CHF 10. It’s quicker to use the decimal: 50 × 0.2 = 10.
The most common values at a glance:
| out of 50 | out of 100 | out of 200 | out of 500 | out of 1,000 | |
|---|---|---|---|---|---|
| 5 % | 2.50 | 5 | 10 | 25 | 50 |
| 10 % | 5 | 10 | 20 | 50 | 100 |
| 20 % | 10 | 20 | 40 | 100 | 200 |
| 25 % | 12.50 | 25 | 50 | 125 | 250 |
| 30 % | 15 | 30 | 60 | 150 | 300 |
Percentage: x out of y as a percentage
What percentage of CHF 60 is CHF 15? Here, you divide the part by the whole: 15 ÷ 60 × 100 = 25 %.
Here’s an example from everyday life: out of your salary of CHF 6,000, CHF 1,800 goes towards rent. That’s 30 %. To find out whether that’s too much, take a look at the Rule of thumb for rent.
Core value: from the part to the whole
CHF 30 is 15 %. How much is that in total? Work it out: 30 × 100 ÷ 15 = CHF 200.
Or using the rule of three: 15 % is CHF 30. So 1 % is equal to 30 ÷ 15 = CHF 2, and 100 % is 2 × 100 = CHF 200.
Here’s what you need to know if you only know the amount saved. If a discount of 25 % saves you exactly CHF 40, the item must have cost CHF 160 previously.
Calculate the percentage change
The formula: (new value − old value) ÷ old value × 100. The previous value is always shown at the bottom. This is exactly where the most common mistake is made.
Your salary will increase from CHF 5,800 to CHF 6,000. That is 200 ÷ 5,800 × 100 = 3.4 % more. You calculate every difference as a percentage in the same way, whether it’s prices, rents or exchange rates.
The gradient in per cent is calculated in the same way: difference in height ÷ horizontal distance × 100. A road with a gradient of 12 % rises by 12 metres over a horizontal distance of 100 metres.
Loss and profit are not the same
If your portfolio falls by 20 %, you’ll then need +25 % to get back to where you were. A loss of −20 % on CHF 10,000 leaves you with CHF 8,000. You are CHF 2,000 short of CHF 10,000, which is 25 % of CHF 8,000.
Percent or percentage points?
If the mortgage interest rate rises from 1.5 % to 2 %, it will have increased by 0.5 percentage points has risen. Expressed as a percentage, that is +33 %. Both are correct, but they mean something different. When it comes to interest rates, tax rates and surveys, percentage points are usually the clearer way of expressing the figure.
At the end of the day, it’s the amount in Swiss francs that counts for your budget: with a mortgage of CHF 600,000, 0.5 percentage points will cost you an extra CHF 3,000 a year.
Tip: In the percentage calculator, simply enter the old and new values in the «Change in %» tab. The calculation process shows you which number appears in the fraction at the bottom.
Calculating discounts and surcharges
To calculate a mark-up, use the base value × (1 + percentage ÷ 100); to calculate a discount, use the base value × (1 − percentage ÷ 100).
- 20 % discount: CHF 149 × 0.8 = CHF 119.20.
- 8.1 % VAT: CHF 200 × 1.081 = CHF 216.20.
- 2 % Pay rise: CHF 6,000 × 1.02 = CHF 6,120.
Discounts cannot be combined
20 % off plus 10 % extra off do not equal 30 %. The second discount is applied to the already reduced price: 100 × 0.8 × 0.9 = 72. So you save 28 %, not 30 %.
Calculate the price before the discount
After a 20 % discount, you paid CHF 119.20. The original price is 119.20 ÷ 0.8 = CHF 149. If, instead, you calculate 119.20 plus 20 %, you end up with CHF 143.04. That sounds logical, but it’s a mistake: the 20 % refer to the old price, not the new one.
Subtract a percentage from the final price
If a surcharge is already included in the price, you must not simply deduct it. The most common example is VAT, which in Switzerland has had a standard rate of 8.1 % since 2024. The current rates are published by the FTA.
How much VAT is there in CHF 108.10? If you calculate 8.1 % from 108.10, you get CHF 8.76. That is incorrect. The correct answer is 108.10 ÷ 1.081 = CHF 100 net. The VAT is therefore CHF 8.10.
The reason: The 8.1 % figures refer to the net price. In the percentage calculator, you should use the «Before mark-up» tab for this. You can find all the rates and both directions at a glance in the VAT calculator.
Calculating percentages in Excel
In Excel or Google Sheets, you don’t need a dedicated percentage function. Six formulas cover almost everything. The first value is always in A1, and the second in B1.
| Task | Formula | Example |
|---|---|---|
| x % of y | =A1*B1 | A1 = 50, B1 = 20; % equals 10 |
| Proportion in % | =B1/A1 | A1 = 60, B1 = 15 gives 25 % |
| Base value | =A1/B1 | A1 = 30, B1 = 15; % equals 200 |
| Change in % | =(B1-A1)/A1 | A1 = 80, B1 = 100 gives 25 % |
| Plus x % | =A1*(1+B1) | A1 = 200, B1 = 8.1; % gives 216.20 |
| Minus x % | =A1*(1-B1) | A1 = 149, B1 = 20; % gives 119.20 |
Format the result cell for ‘Proportion’ and ‘Change’ as a percentage. Important: If you type «20 %» into a cell, Excel will store 0.2. If you then divide this by 100 again, your result will be a hundred times too small.
Calculating percentages in your head
- 10 %: Move the decimal point one place to the left. 10 % of CHF 87 is CHF 8.70.
- 5 %: half of 10 %, i.e. CHF 4.35.
- 1 %: Move the decimal point two places to the left. 1 % of CHF 87 is 87 rappen.
- 25 % and 50 %: a quarter and half.
- Exchange: 8 % out of 50 is the same as 50 % out of 8, which is 4.
If your problem is not expressed as a percentage but as a ratio of three known values, the Rule of three calculator. You can find more tools in the Overview of all calculators.
Where small percentages can prove costly
A discount amounts to just a few francs. Fees on your assets, on the other hand, amount to tens of thousands, because they are charged year after year and slow down the growth of compound interest.
A sample calculation: You invest CHF 50,000 for 20 years; the market yields 5 % per year. With an ETF charging 0.2 % in fees per year, you’ll end up with around CHF 127,700. With a fund charging 1.5 %, the figure is around CHF 99,500. A difference of around CHF 28,000, due to 1.3 percentage points. Not a typo.
«I optimise bank charges. Not every coffee.»
That’s what Eric, the founder of Schwiizerfranke, says, and he’s referring to precisely this calculation. You’ll hardly notice if you save a few per cent on a coffee. But you’ll certainly notice a one per cent fee on your investment account every year. Returns are never guaranteed. Fees, on the other hand, certainly are.
You can work out how much of a difference this makes to your savings plan using the ETF Savings Plan Calculator You can find affordable providers in the Broker comparison. And the Inflation calculator.
Frequently asked questions about calculating percentages
How do you work out percentages?
Divide the part by the whole and multiply by 100. CHF 15 out of CHF 60 is 15 ÷ 60 × 100 = 25 %.
How do I calculate percentages using a calculator?
The % button works differently depending on the device. The safest way is to use the decimal value: 20 % out of 50 is 50 × 0.2 = 10. To add 20 more %, you calculate 50 × 1.2.
How do I work out the difference as a percentage?
(new value − old value) ÷ old value × 100. From 80 to 100 is +25 %. The old value is always shown at the bottom.
How do I work out a 20 per cent discount?
Multiply the price by 0.8. CHF 149 becomes CHF 119.20. You can work out the original price by dividing the final price by 0.8.
How do I work out the VAT from a price?
The gross price divided by 1,081 gives the net price; the difference is the VAT. Of the CHF 108.10, CHF 8.10 is VAT.
How do I work out minus 20 per cent?
Multiply the amount by 0.8. CHF 250 becomes CHF 200. For negative x %, you generally calculate the amount × (1 − x ÷ 100).
How do I calculate percentages in Excel?
Use =A1*B1 for x % of y, =B1/A1 for the proportion, and =(B1-A1)/A1 for the change. Format the result cell as a percentage.
Is the percentage calculator free of charge?
Yes. You don’t need to register, and your figures aren’t stored anywhere.