Basic Calculator

How to Use the Basic Calculator

This calculator handles addition, subtraction, multiplication, division, powers, percentages, and grouped expressions through an on-screen keypad or your physical keyboard. Use the keypad buttons or type directly. Both work the same way. Results appear instantly as you build the expression, and a full history of past calculations is available in the status bar.

Understanding the Display

The display shows your current calculation as a single expression. As you enter numbers and select operations, the display updates to reflect the full calculation in progress (for example, 45 + 32). When you press equals, the result replaces the expression.

Basic Operations

Addition (+)

1. Enter the first number
2. Press +
3. Enter the second number
4. Click to see the result

Example: 45 + 32 = 77

Subtraction (-)

1. Enter the first number
2. Press -
3. Enter the second number
4. Click to see the result

Example: 100 - 35 = 65

Multiplication (×)

1. Enter the first number
2. Press ×
3. Enter the second number
4. Click to see the result

Example: 12 × 8 = 96

Division (÷)

1. Enter the dividend
2. Press ÷
3. Enter the divisor
4. Click to see the result

Example: 144 ÷ 12 = 12

Power (^)

1. Enter the base number
2. Press ^
3. Enter the exponent
4. Click to see the result

Example: 2 ^ 3 = 8

For logarithms (the inverse of powers) and trigonometric functions, use the Scientific Calculator.

Percentage (%)

1. Enter a number
2. Press % to append it as a percentage
3. Continue with another operation, or click

Example: 80 × 20% = 16

Parentheses ( )

1. Press ( to start a grouped expression
2. Enter the inner calculation
3. Press ) to close the group
4. Continue with the rest of the expression, or click

Example: (5 + 3) × 2 = 16

Control Buttons

Clear (C)

Press C to clear all calculations and reset the calculator to zero. Use this to start a completely new calculation.

Clear Entry (CE)

Press CE to clear only the current entry without affecting calculations in progress. Use this if you make a mistake entering the current number.

Backspace ()

Press the button to delete the last digit you entered. Useful for correcting typos without starting over.

Sign Toggle (±)

Press ± to change the sign of the current number from positive to negative, or vice versa.

Keyboard Shortcuts

Calculation History

Recent calculations are saved automatically. Click the History in the status bar to view your calculation history. Each entry shows the full calculation (e.g., "2+2 = 4"). Click the Trash to clear all history.

Common Use Cases

Calculating Tips

15% tip on an $80 bill:

1. Enter: 80 × 0.15 = 12

20% tip using the % key:

1. Enter: 80 × 20% = 16

Splitting Bills

Split a $150 bill among 4 people:

1. Enter: 150 ÷ 4 = 37.5

Budgeting

Track monthly expenses:

• Rent: $1,200
• Utilities: $150
• Groceries: $400

1. Enter: 1200 + 150 + 400 = 1750

Shopping Discounts

Sale price of a $60 item with 25% off:

1. Discount: 60 × 0.25 = 15
2. Final price: 60 - 15 = 45

Or in one step: 60 × 0.75 = 45

Tips for Accurate Calculations

1. Verify numbers first: Check your input before pressing to avoid errors
2. Place decimals carefully: In money calculations, a misplaced decimal causes off-by-one errors
3. Press C to start fresh: Use C or Escape when switching to an unrelated calculation
4. Continue from results: Use the result of a finished calculation rather than retyping it
5. Press CE for mistakes: Clear only the current entry if you make an error mid-expression

Troubleshooting

Display Shows "Error"

This typically means:

• Division by zero was attempted
• The result is too large to display
• An invalid operation was performed

Press C to clear the error and start over.

Result Looks Unexpected

• Check that you pressed between separate calculations
• For chained operations, the calculator continues from the last result. Press C first if you want a fresh start

Calculator Not Responding

• Refresh the page to reset
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