Real-Time Addition Calculator

Instant display of addition results

Simply enter numbers to instantly calculate addition results. Supports negative numbers and decimals. A simple tool that can be used in everyday situations such as education, shopping, and household budgeting.

How to Use

You can perform addition in just 3 steps:

Enter first number
Enter the first number in the left input field. You can enter negative numbers or decimals.
Enter second number
Enter the number to add in the right input field. You can specify any number.
View result
As you type, the sum is automatically calculated and displayed in the result field.

All calculations are performed within your browser and no data is sent to the server.

Addition Calculator

Result (Sum)

Practical Uses of Addition

Addition is used in various situations in daily life:

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What is Addition

Addition is a basic arithmetic operation that combines two or more numbers to find their sum. In mathematics, it is represented by the "+" symbol and is one of the most fundamental operations.

Properties of Addition

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Benefits of This Tool

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Usage Tips

Adding Negative Numbers

You can also enter negative numbers. Example: -5 + 3 = -2, -10 + -5 = -15. Adding a negative number is essentially subtraction.

Decimal Calculations

Accurately calculates numbers with decimal points. Example: 2.5 + 3.7 = 6.2. This tool uses a high-precision calculation library to minimize floating-point errors.

Clear Button

Clicking the "Clear" button resets all input fields and results, returning focus to the first input field.

Keyboard Operation

Move between input fields using the Tab key. You can also fine-tune numbers with arrow keys (↑↓).

Frequently Asked Questions

What happens when I add negative numbers?

Adding a negative number is equivalent to subtracting its absolute value. Example: 10 + (-5) = 5, -3 + (-2) = -5.

Can I calculate with decimals?

Yes, this tool supports decimal addition. Example: 2.5 + 1.75 = 4.25. It uses a high-precision calculation library to minimize floating-point errors.

What is the calculation precision of this tool?

This tool uses a high-precision calculation library (Decimal.js) that provides higher precision than standard floating-point arithmetic. You get accurate results even with large numbers or decimals.

Is my input data saved?

No, all calculations are performed within your browser and no data is sent to the server. Your input numbers are not stored at all, and your privacy is fully protected.

Can I add 3 or more numbers?

This tool supports addition of two numbers. To add 3 or more numbers, first calculate the first two, then add the next number to that result, repeating this process.

Can I use this on a smartphone?

Yes, you can use it on any device including smartphone, tablet, and PC. The responsive design displays an optimal layout based on screen size.

Can I copy the calculation result?

Yes, you can select and copy the number displayed in the result field. Copy with Ctrl+C (Windows) or Cmd+C (Mac) and paste into other applications.

Why is it calculated in real-time?

This tool uses JavaScript to perform calculations within your browser. Since no server communication is required, results are displayed instantly as you type.