Free Online Calculator
Need a quick answer without hunting for your phone's calculator app? This free online calculator handles everyday math right in your browser: addition, subtraction, multiplication, division and percentages, on any device and with nothing to install.
How to Use the Online Calculator
Using the calculator is as simple as using a pocket calculator. Tap or click the number keys, choose an operator, and press the equals key to see the result. If you are on a laptop or desktop, you can usually type directly with your keyboard as well, which makes long chains of numbers much faster to enter.
- Enter the first number.
- Choose an operation: +, −, × or ÷.
- Enter the next number and keep chaining operations if you need to.
- Press = to get the answer, or C to clear and start again.
Why Use a Free Calculator Online?
A browser-based calculator is always one tab away. You do not need to download an app, create an account or worry about storage space. It loads quickly, works on Android, iPhone, tablets, Windows, Mac and Chromebook, and the large buttons are easy to tap on a small screen.
It is also handy when you are already working on a computer. Checking a budget, splitting a restaurant bill, adding up invoice lines or double-checking homework is easier when the calculator sits right next to the document you are working on, instead of switching between devices.
Popular calculators
Everyday Things You Can Calculate
- Shopping and budgets: add up a grocery list or compare the cost of two products.
- Splitting bills: divide a total among friends or roommates in seconds.
- School work: check arithmetic answers and practice mental math.
- Work tasks: total hours, quantities, prices and simple averages.
- Quick percentages: work out a tip or a markup with the % key.
Basic Calculator vs. Specialised Calculators
The basic calculator is perfect for straightforward arithmetic. When a problem needs more than that, a dedicated tool saves time and reduces mistakes. For trigonometry, logarithms and powers, open the scientific calculator. For percent change and "what percent of" questions, the percentage calculator walks you through each case. Shopping during a sale? The discount calculator shows the final price and your savings.
We also offer everyday tools that go beyond math: an age calculator for exact ages between dates, a BMI calculator, a calorie calculator and a salary calculator for converting hourly, monthly and annual pay.
Tips for Accurate Results
Most calculation errors come from typing, not from the math itself. Take a second to check the display before pressing equals, especially with long numbers. Use the clear key when you start a new problem so an old value does not carry over. For expressions that mix several operations, it can help to break the problem into smaller steps or use the scientific calculator, which supports parentheses.
Frequently Asked Questions
Is this online calculator free to use?
Yes. The calculator is completely free, with no sign-up, subscription or hidden limits. You can use it as often as you like for personal, school or work calculations, and all of the other calculators on OnlineCalculadora are free as well.
Does the calculator work on mobile phones?
Yes. The calculator is responsive, so it adapts to phones, tablets and desktop screens. It works in modern browsers such as Chrome, Safari, Firefox and Edge on Android, iPhone, Windows, Mac and Chromebook, with buttons sized for easy tapping.
How do I calculate a percentage with the basic calculator?
To find a percentage of a number, multiply the number by the percentage and divide by 100. For example, 15% of 80 is 80 × 15 ÷ 100 = 12. For percent change or reverse percentages, the dedicated percentage calculator is faster and shows each step.
What order of operations does the calculator use?
Behaviour can vary depending on how expressions are entered. Simple calculators often evaluate each operation as you press it. If your problem mixes multiplication, division, addition and subtraction, work in steps or use the scientific calculator with parentheses to be certain of the order.
Do I need to download anything?
No. The calculator runs directly in your web browser, so there is nothing to download or install. Just open the page and start calculating. You can bookmark the page or add it to your phone's home screen for even quicker access.