This free scientific calculator runs entirely in your browser — no app to install, no account needed. It handles everything from basic arithmetic to trigonometry, logarithms, powers, roots, and mathematical constants like π and e. Use the on-screen keypad or your physical keyboard to build expressions and evaluate them instantly.
How the Scientific Calculator Works
Type or click a number into the display, then apply a function (sin, log, √, etc.) or an operator (+, −, ×, ÷, ^). The expression bar shows your full input before evaluation — press = or Enter to get the result. The calculator follows PEMDAS order of operations automatically, so 3 + 4 × 2 correctly yields 11, not 14. Switch between DEG and RAD mode at the top depending on whether your angles are in degrees or radians. Calculation history is stored below the keypad for the current session.
3 Real-World Examples
Finding the ramp length for a loading dock. Dock height = 1.2m, angle = 15°. Length = 1.2 ÷ sin(15°) = 1.2 ÷ 0.2588 ≈ 4.64 meters. Use sin(angle) for opposite/hypotenuse calculations.
A cell is 0.000045 meters wide = 4.5 × 10⁻⁵. Distance from Earth to Sun ≈ 1.496 × 10¹¹ meters. Use the EXP or × 10ⁿ function to handle very large or small numbers without errors.
At 7% annual return, how many years to double $10,000? Using Rule of 72: 72 ÷ 7 ≈ 10.3 years. Exact answer: log(2) ÷ log(1.07) = 0.301 ÷ 0.0294 ≈ 10.24 years.
Tips
- Always check your angle mode (DEG vs RAD) before running trig functions — a wrong mode is the most common source of unexpected results.
- Use parentheses liberally for complex expressions; they cost nothing and prevent order-of-operations errors.
- For nth roots, use the xʸ button with a fractional exponent: the 4th root of 16 = 16^(1/4) = 2.
- The history panel lets you scroll back through your session — click any past result to reuse it.
Understanding Order of Operations
Scientific calculators evaluate expressions using PEMDAS: Parentheses first, then Exponents, then Multiplication and Division (left to right), then Addition and Subtraction (left to right). This is the universal mathematical convention. A basic left-to-right calculator would give a wrong answer for any mixed expression. If you are ever unsure how a complex expression will be parsed, wrap sub-expressions in parentheses — this is a zero-cost habit that eliminates ambiguity entirely.