Scientific Calculator

Last updated: June 14, 2026

Trig, logs, powers and roots — free online.

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The Scientific Calculator is a free online tool that evaluates full expressions with sin, cos, tan, natural log (ln), base-10 log, square roots, squares, powers (xʸ), π and e. Toggle between degrees and radians for trigonometry, type a whole expression and watch the live answer update as you go. Results are accurate to 10 decimal places and everything runs in your browser — no sign-up, no download, nothing uploaded.

How to use Scientific Calculator

Use the on-screen keypad to build a complete expression instead of one operation at a time. Tap numbers, operators, brackets and functions like sin, ln or √, and a grey preview line shows the running result while you type. Set DEG or RAD first so your trig answers are correct, then press = to lock in the final value.

Read the full guide: How to Use a Scientific Calculator (Free, Online)

  1. 1Pick DEG or RAD at the top — this decides whether sin, cos and tan read your angle in degrees or radians.
  2. 2Build the expression with the keypad: digits, + − × ÷, brackets, and functions such as sin(, cos(, ln(, log(, √(, x², xʸ, π and e.
  3. 3Watch the live preview under your input update the answer as you type, then press = to commit the result (it carries into your next calculation).
  4. 4Use AC to clear everything, ⌫ to delete the last entry, or ± to wrap the current expression in a negative.

Degrees or radians

One tap switches trig mode, so sin(30) returns 0.5 in DEG and the radian value in RAD without any manual π/180 conversion.

Full-expression entry

Type something like 2×(sin(45)+√9)^2 in one line with brackets and see it evaluate by standard order of operations.

Private and instant

Every calculation runs in JavaScript on your device — no account, no network request, and nothing you enter ever leaves the browser.

Trigonometry homework in degrees

Math and physics problems usually give angles in degrees. Leave the calculator in DEG, type sin(30), cos(60) or tan(45), and you get 0.5, 0.5 and 1 directly — no need to convert to radians by hand. Combine functions inside one expression, like sin(45)^2 + cos(45)^2, to check identities quickly.

Logarithms for pH and decibels

Switch between natural and base-10 logs for chemistry and engineering. Use log for a pH estimate from hydrogen-ion concentration or for converting a power ratio to decibels (10 × log of the ratio), and use ln for exponential decay, half-life and continuous-growth problems where the base is e.

Powers and roots for geometry

Compute areas, volumes and distances that need exponents and roots. Square a radius with x², raise to higher powers with xʸ, and take square roots with √ — for instance the hypotenuse from √(3^2 + 4^2) returns 5. Brackets let you nest the whole calculation in a single line.

Quick percentage and constant work

Drop π straight into a circle formula such as π×5^2 for area, pull in e for compound-growth models, and use the % key to turn 15% into 0.15 inside a larger sum. The running preview means you see each intermediate answer before committing with =.

Scientific Calculator — frequently asked questions

Does it calculate in degrees or radians?

Both. The DEG/RAD toggle at the top sets the mode. In DEG, trig functions treat your input as degrees (sin, cos, tan multiply the angle by π/180 internally); in RAD they use the raw radian value. Inverse trig is not included in this version.

What's the difference between ln and log here?

ln is the natural logarithm (base e), so ln(e) = 1. log is the common logarithm (base 10), so log(1000) = 3. Both expect a positive number; a zero or negative argument returns Error.

How accurate are the results?

Calculations use the browser's native double-precision (IEEE 754) math, and the displayed answer is rounded to 10 decimal places. That removes tiny floating-point artefacts like 0.30000000000000004 while keeping results exact for everyday use.

How do I enter powers, squares and roots?

Tap x² to square the current value, xʸ to raise a number to any exponent (it inserts ^), and √ for square root. For example 2 xʸ 10 = 1024, and √(2) ≈ 1.4142135624.

What do π, e and % do?

π inserts 3.14159… and e inserts Euler's number 2.71828…, both usable mid-expression. The % key divides the preceding value by 100, so 50% becomes 0.5.

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