Free online scientific calculator

How to use

1. Type numbers using the buttons or your keyboard.
2. Press a function button (sin, log, √, etc.) to apply it to the current value instantly.
3. For binary operations (×, +, −, ÷, xʸ), enter the first number, press the operator, enter the second number, then press =.
4. Use the expression display at the top to track your running calculation.

Supported operations

Keyboard shortcuts

Worked examples

sin(45°) — degrees mode

1. Make sure DEG is selected (top toggle).
2. Press 4 5 then sin.
3. Result: 0.7071067812 (= √2 / 2)

Natural log of 10

1. Press 1 0 then ln.
2. Result: 2.302585093

Useful because ln(10) ≈ 2.303 is the bridge between the two log bases: log₁₀(x) = ln(x) / ln(10).

Compound a $10,000 investment at 7% for 20 years

Formula: A = P × (1 + r)ⁿ

1. Enter 1.07 then press xʸ.
2. Enter 20 then press =. Result: 3.8697
3. Multiply by 10000 → =. Result: $38,697

8! (factorial)

1. Enter 8 then press n!.
2. Result: 40,320 (8 × 7 × 6 × 5 × 4 × 3 × 2 × 1)

Notes

• DEG vs. RAD — the most common source of wrong answers. If sin(90) returns 0.894 instead of 1, you’re in RAD mode and need to switch to DEG.
• Operator precedence — this calculator evaluates left-to-right as you type, like a standard physical scientific calculator. For strict algebraic order (PEMDAS), group with parentheses or compute inside expressions step by step.
• Results are rounded to 10 significant digits to avoid floating-point noise.
• Factorial is limited to integers 0–170. Above 170, factorial exceeds JavaScript’s maximum float.
• The calculator is stateless — there is no URL sharing because there are no persistent inputs.