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Scientific Calculator

A full scientific calculator that evaluates trig, logs, powers, roots and factorials right in your browser — no sign-up, no server round-trip.

Privacy: your files never leave your device. All processing happens locally in your browser.

How to use

  1. 1.Type a math expression into the display (for example sin(45) + 2^3), or tap the on-screen keys to build it — digits, operators, functions, pi and e are all available.
  2. 2.Set the DEG / RAD toggle to choose whether angles are read as degrees or radians; the result re-calculates instantly when you switch.
  3. 3.Watch the live preview update as you type, then press = (or Enter) to commit the final answer. Use C to clear or the backspace key to delete the last character.

About Scientific Calculator

This free online scientific calculator evaluates full mathematical expressions directly in your browser — nothing is uploaded to a server, so every calculation is instant and private. Type an expression like sin(45) + 2^3 into the display, or tap the on-screen keypad, and the result updates live as you type. Press = to lock in the answer.

It understands the operators + - * / and ^ for exponents, plus parentheses for grouping and a unary minus for negative values. A hand-written expression parser applies the standard order of operations (PEMDAS / BODMAS): parentheses first, then exponents, then multiplication and division, and finally addition and subtraction. Exponentiation is right-associative, so 2^3^2 evaluates as 2^(3^2) = 512, matching the mathematical convention used by most scientific calculators.

Supported functions cover the essentials of trigonometry, algebra and analysis: sin, cos and tan; the inverse trig functions asin, acos and atan; the natural logarithm ln and the base-10 logarithm log; sqrt for square roots; exp for e raised to a power; and abs for absolute value. A DEG / RAD toggle controls how angles are interpreted — in degree mode sin(90) returns 1 and asin(1) returns 90, while in radian mode sin(pi/2) returns 1. The whole expression is re-evaluated the moment you flip the toggle.

The calculator also supports the postfix factorial operator, so 5! returns 120; factorials are defined only for non-negative integers and the tool reports a clear error for anything else. Two mathematical constants are built in: pi (approximately 3.14159) and e (approximately 2.71828), which you can combine freely with any operator, for example 2*pi.

Because the parser requires explicit operators, implicit multiplication such as 2pi is not accepted — write 2*pi instead. Invalid input never crashes the tool: an empty expression, a trailing operator, mismatched parentheses, an unknown function name, or an out-of-domain value simply shows an error message so you can correct it.

Everything runs locally using your device's own math engine, which means there is no rate limit, no login, and no network latency. It works offline once the page has loaded and is well suited to homework, engineering estimates, quick trig checks, and any situation where you need a dependable scientific calculator without installing an app. Bookmark it as a fast, no-friction alternative to a physical calculator or a phone app.

Frequently asked questions

Does it support degrees and radians?
Yes. Use the DEG / RAD toggle to switch angle units. In degree mode sin(90) equals 1 and asin(1) returns 90; in radian mode sin(pi/2) equals 1. The expression is re-evaluated the instant you flip the toggle.
What order of operations does it use?
It follows standard PEMDAS / BODMAS: parentheses first, then exponents, then multiplication and division, then addition and subtraction. Exponentiation is right-associative, so 2^3^2 evaluates as 2^(3^2) = 512.
Which functions and constants are built in?
Trigonometry (sin, cos, tan, asin, acos, atan), logarithms (ln for natural log, log for base 10), plus sqrt, exp, abs, and the postfix factorial operator (5! = 120). The constants pi and e are available and can be combined with any operator.
Is my data sent anywhere?
No. Every expression is parsed and evaluated locally in your browser using your device's own math engine. Nothing is uploaded to a server, there is no login and no rate limit, and it keeps working offline once the page has loaded.
Why does 2pi give an error?
The calculator requires explicit operators and does not assume implicit multiplication, so 2pi is rejected — write 2*pi instead. This keeps parsing unambiguous. Invalid input such as mismatched parentheses or an unknown function name shows an error message rather than a wrong answer.

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