Free Online Scientific Calculator
This free scientific calculator runs entirely in your browser and handles everything a handheld scientific calculator does — trigonometry, logarithms, exponents, roots, factorials, constants like π and e, memory functions, and scientific notation — with no app to download and no signup. You can either click the on-screen buttons or type directly with your keyboard, and the calculator follows the standard order of operations so complex expressions evaluate exactly as you intend. It works on phones, tablets, and computers, making it a reliable stand-in for a physical calculator in algebra, trigonometry, calculus, physics, chemistry, statistics, and engineering.
Complete Function Reference
Unlike a basic four-function calculator, a scientific calculator gives you a full keypad of advanced operations. Here is what each function does:
| Function | What It Does |
|---|---|
| sin, cos, tan | Trigonometric functions of an angle |
| sin⁻¹, cos⁻¹, tan⁻¹ | Inverse trig — find the angle from a ratio |
| log | Base-10 logarithm |
| ln | Natural logarithm (base e) |
| eˣ, 10ˣ | Exponential functions |
| x², x³, xʸ | Squares, cubes, and arbitrary powers |
| √x, ³√x, ʸ√x | Square root, cube root, and nth root |
| n! | Factorial (product of all integers up to n) |
| 1/x | Reciprocal |
| % | Percentage |
| π, e | Built-in constants (3.14159…, 2.71828…) |
| ( ) | Parentheses for grouping |
| EXP | Enter scientific notation (e.g., 6.02 EXP 23) |
| ± | Change sign (positive/negative) |
| Ans | Reuse the previous answer |
| M+, M−, MR | Memory add, subtract, and recall |
| Deg / Rad | Switch the angle mode |
How to Use the Scientific Calculator
- Type or click: enter numbers and operators with your keyboard or the on-screen keypad.
- Use parentheses generously to control grouping in long expressions.
- Set the angle mode (degrees or radians) before using any trig function.
- Press equals to evaluate, and use Ans to carry the result into your next calculation.
Order of Operations (PEMDAS)
The calculator automatically applies the standard order of operations: Parentheses, Exponents, Multiplication and Division (left to right), then Addition and Subtraction (left to right). This means an expression like 2 + 3 × 4 evaluates to 14, not 20, because multiplication is performed before addition. When you want a different order, wrap the part you want done first in parentheses — for example, (2 + 3) × 4 = 20. Relying on the calculator's built-in precedence, combined with liberal use of parentheses, eliminates the most common source of wrong answers.
Degrees vs Radians: Get This Right First
Trigonometric functions return completely different results depending on the angle mode, so this is the single most important setting to check. Degrees divide a full circle into 360 parts and are standard in geometry and everyday angle measurement. Radians measure angles by arc length and are the default in calculus and physics, where a full circle is 2π radians. For example, sin(90) equals 1 in degree mode but about 0.894 in radian mode — a difference that quietly ruins homework and lab work. Always confirm Deg or Rad before evaluating sin, cos, tan, or their inverses.
| Angle | Degrees mode | Radians mode |
|---|---|---|
| sin(30) | 0.5 | −0.988 |
| cos(0) | 1 | 1 |
| tan(45) | 1 | 1.6198 |
Memory Functions Explained
Memory keys let you store and reuse a running value without writing it down. M+ adds the displayed number to memory, M− subtracts it, and MR recalls the stored total. This is ideal for multi-part problems — for instance, totaling several subtotals, or holding a constant you reference repeatedly across a calculation. The Ans key is related but distinct: it inserts the result of your last calculation, so you can chain operations naturally.
Working with Scientific Notation
For very large or very small numbers, use the EXP (or ×10ˣ) key to enter scientific notation. Typing 6.02 EXP 23 represents 6.02 × 10²³ (Avogadro's number), and 1.6 EXP −19 represents 1.6 × 10⁻¹⁹. This keeps long strings of zeros manageable and is essential in chemistry and physics. The calculator also displays results in scientific notation automatically when a number is too large or too small to show in full.
Worked Examples
- Trigonometry: the height of a tree from a 30° angle and 50 m distance: 50 × tan(30°) ≈ 28.9 m (degree mode).
- Logarithms: log(1000) = 3, and ln(e) = 1.
- Compound growth: 1000 × (1.05)¹⁰ ≈ 1628.89 using the xʸ key.
- Combinatorics: 5! = 120 using the factorial key.
- Roots: ³√27 = 3 using the cube-root function.
Common Mistakes to Avoid
- Wrong angle mode — the number-one error; always check Deg vs Rad first.
- Missing parentheses — especially around negative bases and fractions.
- Confusing log and ln — log is base 10, ln is base e.
- Forgetting order of operations — let the calculator handle precedence and group with parentheses when needed.
Scientific vs Basic vs Graphing Calculators
A basic calculator only adds, subtracts, multiplies, and divides. A scientific calculator adds trig, logs, exponents, roots, factorials, constants, and scientific notation — everything covered above. A graphing calculator goes further still, plotting functions and solving equations visually. For most school and exam math through calculus, a scientific calculator is exactly the right tool, which is why it remains the standard for classrooms and standardized tests.
Frequently Asked Questions
What can a scientific calculator do that a basic one cannot?
It adds trigonometry, logarithms, exponents, roots, factorials, scientific notation, constants like π and e, and memory functions, plus automatic order-of-operations handling for complex expressions.
How do I switch between degrees and radians?
Use the Deg/Rad toggle before evaluating any trig function. Degrees suit geometry and everyday angles; radians are standard in calculus and physics. The same angle gives different results in each mode.
What is the difference between log and ln?
"log" is the base-10 logarithm, while "ln" is the natural logarithm with base e (about 2.718). Both measure how many times a base is multiplied to reach a number.
How do I calculate a factorial?
Enter the number and press the factorial (n!) key. A factorial multiplies every whole number from 1 up to that number — for example, 6! = 720.
How do I enter very large or very small numbers?
Use the EXP (or ×10ˣ) key for scientific notation. For example, 3.0 EXP 8 represents 3 × 10⁸, the speed of light in meters per second.
What do M+, M−, and MR do?
M+ adds the current value to memory, M− subtracts it, and MR recalls the stored total — useful for accumulating subtotals across a multi-step problem.
Can I use my keyboard instead of clicking?
Yes — you can type numbers, operators, and parentheses directly. The buttons and keyboard input are interchangeable.
Why does my trig answer look wrong?
Almost always it is the angle mode. Check whether you are in degrees or radians, since the same function returns very different values in each.
Is this scientific calculator accurate for exams and homework?
Yes — it follows standard mathematical precedence and supports the full range of scientific functions used through calculus, physics, and chemistry coursework.
Is this scientific calculator free?
Yes — it is completely free, runs in your browser on any device, and requires no signup or download.