Basic Calculator Online: Free Math Tool with History & Memory
Free online basic calculator with order of operations (PEMDAS), calculator with memory and history. Basic calculator that follows PEMDAS, keyboard shortcuts, and percentage. No sign-up, works offline.
What Is a Basic Calculator? Free Online Calculator with Order of Operations
A basic calculator is a tool for everyday arithmetic: addition, subtraction, multiplication, division, and percentage. This free online basic calculator goes further: it follows order of operations (PEMDAS), so expressions like 3 + 5 ร 2 give 13, not 16. It includes a calculator with memory (MC, MR, MS, M+, M-) and a history tape of your last calculations, plus full keyboard support and intelligent formatting (thousands separators, scientific notation for very large or small numbers). Use it as a basic calculator for school, work, or quick mathโno sign-up, no ads, and all calculations stay in your browser.
Why Use Our Basic Calculator?
Premium Features Without the Price
- Uncluttered Interface:Clean, optimized interface that loads instantly and works offline
- Privacy First:All calculations happen locally in your browserโno data sent to servers
- Accessibility:Full ARIA labeling and keyboard support for 100% screen reader compatibility
- High Precision:Uses decimal.js library to avoid floating-point errors (0.1 + 0.2 = 0.3 exactly)
Our basic calculator includes features that premium physical calculators charge extra for: persistent calculation history, full memory suite, PEMDAS order of operations, and intelligent number formatting. All completely free, with no ads, no tracking, and no data collection. Your calculations stay private and secure.
Memory Functions Explained: How to Use Calculator Memory (MC, MR, MS, M+, M-)
Memory Clear (MC)
- When to Use:Starting fresh calculations or clearing stored values before new work
- Visual Indicator:The "M" badge disappears when memory is cleared
Resets the memory register to zero and clears the memory indicator. Use this when starting a new calculation sequence that doesn't need previous memory values.
Memory Recall (MR)
- When to Use:Retrieving a previously stored value for use in a new calculation
- Keyboard Shortcut:Press "M" key for quick memory recall
Displays the current value stored in memory. This replaces the current display with the memory value, useful for retrieving stored intermediate results.
Memory Store (MS)
- When to Use:Storing a calculated result for later use in multi-step calculations
- Keyboard Shortcut:Press "Shift+M" to store current value to memory
Saves the current display value to memory, replacing any previous memory value. The memory indicator appears to show that memory contains a value.
Memory Add (M+) and Memory Subtract (M-)
- When to Use:Building running totals, tracking expenses, or accumulating values across multiple calculations
- Example:Calculate 10 + 5, press M+, calculate 20 + 3, press M+, then MR shows 38 (the sum of both results)
Adds or subtracts the current display value from the memory register. This is useful for accumulating totals or tracking running balances.
Order of Operations (PEMDAS): Calculator That Follows PEMDAS
How PEMDAS Works
- Example 1:3 + 5 ร 2 = 13 (multiplication first: 5 ร 2 = 10, then 3 + 10 = 13)
- Example 2:10 - 4 รท 2 = 8 (division first: 4 รท 2 = 2, then 10 - 2 = 8)
- Example 3:2 ร 3 + 4 ร 5 = 26 (multiplications first: 2ร3=6 and 4ร5=20, then 6+20=26)
- Why It Matters:Without PEMDAS, 3 + 5 ร 2 would incorrectly equal 16. Our calculator ensures mathematical accuracy.
PEMDAS stands for Parentheses, Exponents, Multiplication/Division, Addition/Subtraction. This calculator correctly processes expressions in this orderโa calculator that follows PEMDASโmatching how mathematical expressions are evaluated in algebra and higher mathematics.
Percentage Calculations
- Percentage Of:Enter 100, press ร, enter 10, press % to get 10 (10% of 100)
- Percentage Conversion:Enter 0.15, press % to convert to 15% (0.15 ร 100)
- Real-World Use:Calculate discounts, tax rates, tips, and percentage changes with precision
The percentage button (%) converts the current display to a percentage by dividing by 100. This handles both percentage-of calculations and percentage-change scenarios.
Keyboard Shortcuts & Accessibility
Full Keyboard Support
- Numbers:Type 0-9 to enter digits
- Operators:Use +, -, *, / for arithmetic operations
- Calculate:Press Enter or = to get the result
- Clear:Press Esc or C to clear all, Backspace to delete last digit
- Memory:Press M for recall, Shift+M for store
- Special:Press % for percentage, . for decimal point
Every function is accessible via calculator keyboard shortcuts, making it fast for desktop users and essential for accessibility. No mouse required.
Screen Reader Compatibility
- ARIA Labels:All buttons include descriptive aria-label attributes
- Display Announcements:The calculator display announces results to screen readers
- Keyboard Navigation:Complete keyboard support means no mouse required
- WCAG 2.1 AA Compliant:Meets current accessibility standards for modern web applications
Full ARIA labeling ensures 100% compatibility with screen readers like NVDA, JAWS, and VoiceOver. Every button, display, and function is properly labeled for accessibility.
Intelligent Number Formatting
Thousands Separators
- Automatic Formatting:Numbers with 4+ digits get comma separators (1,234,567)
- Decimal Support:Decimal numbers maintain precision while formatting (1,234.567)
- Input Flexibility:You can type numbers with or without commasโthe calculator handles both
Large numbers are automatically formatted with comma separators for readabilityโe.g. 1,000,000 instead of 1000000. Useful for finance, totals, and any basic calculator result with many digits.
Scientific Notation
- Large Numbers:Values greater than 1,000,000,000,000,000 display in scientific notation (e.g., 1.23e+15)
- Small Numbers:Values less than 0.000001 (but greater than 0) display in scientific notation (e.g., 1.23e-6)
- Precision:Scientific notation maintains full precision for accurate calculations
For extremely large or small numbers, the calculator automatically switches to scientific notation to maintain accuracy and readability.
FAQ
? How do I use the memory functions (MC, MR, MS, M+, M-)?
The memory suite allows you to store and manipulate values: MC (Memory Clear) resets memory to zero, MR (Memory Recall) displays the stored value, MS (Memory Store) saves the current display to memory, M+ adds the current display to memory, and M- subtracts the current display from memory. The "M" indicator appears when memory contains a non-zero value. Use memory for multi-step calculations or storing intermediate results.
? Does the calculator follow order of operations (PEMDAS)?
Yes! Our calculator correctly processes expressions using PEMDAS (Parentheses, Exponents, Multiplication/Division, Addition/Subtraction). For example, 3 + 5 ร 2 = 13 (not 16), because multiplication is performed before addition. This matches how scientific calculators and modern math tools work, unlike basic physical calculators that process operations left-to-right.
? How do I view my calculation history?
Click the "Show History" button above the display to view your last 10 calculations. The history tape shows both the expression and result for each calculation, making it easy to review previous work or copy values for new calculations. The history automatically updates as you perform calculations and persists until you clear it or refresh the page.
? Can I use keyboard shortcuts?
Yes! Full keyboard support is available: type numbers (0-9), operators (+ - * /), press Enter or = to calculate, Backspace to delete, Esc or C to clear, M for memory recall, Shift+M for memory store, and % for percentage. This makes the calculator fast and efficient for desktop users.
? How does the calculator handle very large or small numbers?
The calculator automatically switches to scientific notation for extremely large numbers (greater than 1,000,000,000,000,000) or very small numbers (less than 0.000001). For normal-sized numbers, it displays with thousands separators (commas) for readability. For example, 1,000,000 instead of 1000000. This ensures accurate display regardless of number size.
? What makes this calculator different from basic physical calculators?
Unlike basic physical calculators, this tool includes: persistent history tape (last 10 calculations), full memory suite (MC, MR, MS, M+, M-), PEMDAS order of operations (correctly handles 3 + 5 ร 2 = 13), keyboard shortcuts for desktop productivity, intelligent formatting (thousands separators, scientific notation), and 100% accessibility with full ARIA labels for screen readers.