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Scientific Calculator

Type or tap a whole expression and see the answer as you go — sin, cos, tan, logs, powers, roots, factorials, nCr and more, with DEG/RAD modes, memory and a history you can reuse.

Runs in your browser Free · no sign-up

At a glance

  • Evaluates whole expressions with the correct order of operations and brackets — for example 2sin(30) + √(16+9) × 3² — and shows the answer as you type.
  • Trigonometry in degrees, radians or gradians, with inverse and hyperbolic functions; exact at the special angles (sin 180° = 0, cos 90° = 0, tan 45° = 1).
  • Logs (log, ln, log₂, any base), powers and roots, factorial, nCr and nPr, mod, absolute value, gcd, lcm, π, e and random numbers.
  • Answers show up to 12 significant digits, as a fraction when one fits (0.75 = 3/4), in fixed, scientific or engineering notation, with international or Indian digit grouping.
  • Memory keys (MS, MR, M+, M−, MC), an Ans key and a history of your last 50 calculations that you can edit or reuse.
  • Explains mistakes in plain words — “Can’t divide by zero”, “A ) is missing here” — and marks where. Everything runs in your browser.

Step by step

How to use the scientific calculator

  1. 1

    Pick the angle unit

    Choose DEG for degrees or RAD for radians before using sin, cos or tan.

  2. 2

    Enter the expression

    Tap the keys or type — for example sin(30) + 5². Use 2nd for inverse functions such as sin⁻¹ and hyp for sinh, cosh and tanh.

  3. 3

    Press =

    The answer appears below the expression and is stored as Ans.

  4. 4

    Carry on

    Press an operator to continue from the answer, or pick an earlier calculation from the history.

Features

Everything you need, nothing you don’t

See it as you type

The result updates live, and the expression stays on screen so you can fix a typo instead of starting again.

Keyboard and touch

Tap the keys on a phone, or type on a computer — sqrt(2), pi, 5!, 2^10 all work.

Smart percent

200 + 10% gives 220 and 200 × 10% gives 20, the way you expect.

Natural writing

Write 2π, 3(4+5) or 2sin(30) without a multiplication sign; a missing closing bracket is added for you.

Fractions

Decimal answers that are simple fractions are also shown as p/q.

History and memory

Reuse earlier results, and keep a running total in memory. They are saved on this device.

Keys and what to type

To calculateEnterResult
Square root√(144)12
Any rootroot(32, 5)2
Power2^101024
Sine in degreessin(30)0.5
Inverse tangenttan⁻¹(1)45
Log to any baselog(8, 2)3
Combinations5C210
Percent increase200 + 10%220
Scientific notation6.02E23 × 21.204 × 10²⁴

Order of operations

The calculator follows the standard order: brackets first, then functions and factorials, powers (right to left, so 2^3^2 = 2^9), multiplication and division from left to right, and finally addition and subtraction. A minus sign in front applies after powers, so −2² = −4 while (−2)² = 4.

Multiplication written without a sign (2π, 3(4+5)) has the same priority as ×, so 1 ÷ 2π means (1 ÷ 2) × π. Add brackets — 1 ÷ (2π) — when you mean the other.

FAQ

Frequently asked questions

Why does sin(30) give −0.988 instead of 0.5?

The calculator is in radians. Switch to DEG above the keys — the current unit is shown at the top left of the display.

How do I calculate sin⁻¹, cos⁻¹ or tan⁻¹?

Press 2nd and the sin, cos and tan keys become their inverses. You can also type asin(0.5), acos(0.5) or atan(1).

What is the difference between log and ln?

log is the base-10 logarithm (log 1000 = 3) and ln is the natural logarithm to base e (ln e = 1). For another base type log(x, base), for example log(8, 2) = 3.

How does the % key work?

After + or −, a percentage is taken of the first number: 200 + 10% = 220 and 200 − 10% = 180. Otherwise it divides by 100: 200 × 10% = 20, and 50% = 0.5.

How accurate is it?

It calculates with about 15–16 significant digits and shows 12, which hides the tiny rounding errors of binary arithmetic (0.1 + 0.2 shows 0.3). Factorials work up to 170!.

Is my history saved?

Yes, in this browser only — your last 50 calculations, the memory value and your settings. Press Clear in the history to remove them.

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