🧮 Calculators

Scientific Calculator

A real maths engine (no eval()), a running tape you can edit and recalculate, unit-aware and base conversions, plus graphing, equation solving, matrices, and statistics.

  • ✅ Free forever
  • 🔒 Nothing uploaded
  • 📶 Works offline
  • ⌨️ Keyboard-first
  • 📝 Editable tape
🔒 Runs entirely in your browser and works offline — your calculations, tape, and variables are never uploaded.
 
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Tape Total: 0

Drag to pan, scroll/pinch to zoom. Click on a curve to trace values.

Enter coefficients and press Solve.

Matrix A

Matrix B

Build grids, fill in values, and choose an operation.
Pick dates above.

Free, private, and built for real work

💸 Free, no signupNo account, no trial, no paid tier, no limit on calculations.
🔒 Nothing is uploadedExpressions are parsed and evaluated in your browser. Open DevTools → Network and run a calculation: nothing carrying your numbers leaves the page.
🧮 A real parser, not eval()Expressions are tokenised and evaluated by a proper maths library, so precedence, parentheses and functions behave correctly — and no code you type can execute.
📶 Works offlineA service worker caches the app and the engine after your first visit.
⌨️ Keyboard-firstType the whole expression. Enter evaluates, Escape clears, Backspace deletes.
📝 Editable tapeChange any past line and every line after it recalculates in order.

What is a scientific calculator?

A scientific calculator is one that understands mathematical structure, not just a sequence of keypresses. A basic four-function calculator processes what you type in the order you type it: press 2 + 3 × 4 = and many of them answer 20, because they add 2 and 3 first and then multiply. A scientific calculator answers 14, because multiplication binds tighter than addition. That single difference is what makes it a mathematical instrument rather than an adding machine.

Beyond precedence, a scientific calculator adds the function set that secondary-school and university mathematics actually requires: trigonometry, logarithms, exponents and roots, factorials, scientific notation, and constants such as π and e. This one also carries an editable tape, unit-aware arithmetic, base conversion, an equation solver, matrices and statistics — but the core is the same: type an expression the way it is written on paper, and get the mathematically correct answer.

How to use this calculator

  1. Type the expression. The input accepts ordinary mathematical notation — sin(45) + ln(2)^3 works as written. You do not have to press buttons; the keypad is there when you want it.
  2. Watch the preview. The line under the input evaluates as you type, so you can see a mistake before you commit to it. Unclosed brackets are counted and reported.
  3. Check the angle mode. DEG, RAD or GRAD is shown in brass at the top left. This is the setting that causes the most wrong answers in the world; see below.
  4. Press Enter. The result lands on the tape with its expression.
  5. Reuse anything. Click a past result to insert it into the current expression, or edit a past line to recalculate everything downstream of it.

Scientific calculator functions explained

Scientific calculator functions with worked examples
FunctionType asExampleResult
Sinesin(x)sin(30) in DEG0.5
Cosinecos(x)cos(60) in DEG0.5
Tangenttan(x)tan(45) in DEG1
Inverse sineasin(x)asin(0.5) in DEG30
Hyperbolic sinesinh(x)sinh(0)0
Common log (base 10)log10(x)log10(1000)3
Natural log (base e)log(x)log(e)1
Log to any baselog(x, b)log(8, 2)3
Square rootsqrt(x)sqrt(144)12
Cube rootcbrt(x)cbrt(27)3
nth rootnthRoot(x, n)nthRoot(32, 5)2
Powerx^y2^101024
Exponentialexp(x)exp(1)2.718281828…
Factorialx!6!720
Absolute valueabs(x)abs(-7)7
Combinationscombinations(n, k)combinations(5, 2)10
Permutationspermutations(n, k)permutations(5, 2)20
Moduloa mod b17 mod 52
Round / floor / ceilround(x)ceil(4.1)5
Constantspi, e2 * pi6.283185307…
One naming trap worth knowing. In this engine, as in most programming maths libraries, log(x) is the natural logarithm and log10(x) is the base-10 one. On a physical Casio or TI, the log key is base 10 and ln is natural. If a logarithm answer looks wrong by a factor of about 2.303, this is why — that factor is ln(10).

Degrees, radians and gradians

Angle mode is the most common source of wrong answers on any scientific calculator, and it is worth understanding rather than memorising. All three units measure the same thing — how far round a circle you have gone — they just divide the circle differently.

Angle modes compared
ModeA full circle isUse it forsin of a right angle
DEG360 degreesSchool geometry, surveying, navigation, most engineering drawingssin(90) = 1
RAD2π ≈ 6.283 radiansCalculus, physics, anything where you differentiate a trig functionsin(pi/2) = 1
GRAD400 gradiansSome surveying and civil engineering traditions, mostly Europeansin(100) = 1

The trap is that a wrong mode does not produce an error — it produces a plausible-looking wrong number. sin(30) is 0.5 in degrees and about −0.988 in radians. Both are valid sines; only one answers the question you meant. Radians are not an arbitrary alternative: they are the unit in which the derivative of sin(x) is cos(x). Use degrees for geometry, radians for calculus, and check the brass indicator before you trust a trig result.

Calculating sin, cos and tan

In a right-angled triangle, sine is opposite over hypotenuse, cosine is adjacent over hypotenuse, and tangent is opposite over adjacent — the mnemonic is SOH-CAH-TOA. To find an angle rather than a ratio, use the inverse functions: asin(0.5) returns 30 in DEG mode. Note that tan is undefined at 90° and 270°, where the adjacent side has length zero; the calculator will return a very large number rather than an error, because floating-point 90° is not exactly a right angle.

How logarithms work

A logarithm answers the question "what power do I raise this base to, in order to get this number?" So log10(1000) = 3, because 10³ = 1000. And log(e) = 1, because e¹ = e.

Base 10 is used wherever quantities span many orders of magnitude — the decibel scale, pH, the Richter scale. Base e, the natural logarithm, is used wherever something grows or decays in proportion to its own size: compound interest, radioactive decay, population models, and every integral of 1/x. For any other base, log(x, b) takes it directly — log(8, 2) = 3.

Three rules do most of the work: log(ab) = log(a) + log(b), log(a/b) = log(a) − log(b), and log(aⁿ) = n·log(a). That last one is why logarithms turn awkward exponent problems into ordinary arithmetic, and why slide rules worked.

Powers, roots and reciprocals

Use ^ for any exponent: 2^10 = 1024. Roots are fractional powers, so sqrt(x) is the same as x^(1/2) and cbrt(x) is x^(1/3). For anything else, nthRoot(32, 5) = 2.

Two details that trip people up. First, -2^2 is −4, not 4: the exponent binds tighter than the unary minus, so it reads as −(2²). Write (-2)^2 if you mean 4. Second, exponentiation is right-associative, so 2^3^2 is 2^(3²) = 2⁹ = 512, not (2³)² = 64. That is the standard mathematical convention, and it is what this engine does.

Square roots of negative numbers return a complex result rather than an error, since the underlying engine supports complex arithmetic — sqrt(-4) gives 2i. If you are working strictly in the reals, treat that as a signal that something upstream is wrong.

How factorials work

The factorial of a whole number is that number multiplied by every whole number below it: 5! = 5 × 4 × 3 × 2 × 1 = 120. It counts the number of ways to arrange n distinct things in order, which is why it sits at the heart of probability and combinatorics.

By definition 0! = 1 — there is exactly one way to arrange nothing. Factorials grow ferociously: 10! is 3,628,800, 20! is about 2.4 × 10¹⁸, and 171! exceeds what a double-precision number can represent at all. Beyond about 21! the result stops being exact even though it still displays, because it has passed the point where consecutive integers are representable.

For counting problems, prefer the dedicated functions over building factorials by hand: combinations(5, 2) = 10 for selections where order does not matter, permutations(5, 2) = 20 where it does.

Scientific notation

Scientific notation writes a number as a value between 1 and 10 multiplied by a power of ten, which is the only sane way to handle the quantities physics and chemistry deal in. Avogadro's constant is 6.022 × 10²³; the mass of an electron is about 9.109 × 10⁻³¹ kg.

Type it with e: 6.022e23. The display switches to scientific notation automatically once a result passes 10¹⁵ or drops below 10⁻⁹, because at that point the digit string becomes unreadable and the exponent is the part that matters. You can change where those thresholds sit, and how many decimal places are shown, in the settings panel.

Precision and floating-point

Computers store numbers in binary, and some decimal fractions have no exact binary representation — the same way 1/3 has no exact decimal one. That is why 0.1 + 0.2 evaluates to 0.30000000000000004 in raw JavaScript, and why calculators that display raw values look broken.

This calculator rounds for display at a configurable number of decimal places, defaulting to 10, so 0.1 + 0.2 shows as 0.3 while 1/3 still shows ten meaningful digits. Rounding happens only in the display layer; the value carried onto the tape and into the next calculation keeps its full precision, so errors do not accumulate.

An honest limit. This engine uses standard double-precision floating point, which gives about 15–17 significant decimal digits. That is more than enough for engineering, physics and school mathematics, but it is not arbitrary precision. If you need 50 digits of π, this is the wrong instrument.

Memory, variables and the tape

Three different ways to keep a number, and they are worth distinguishing.

Memory is the classic MC/MR/M+/M− behaviour: one or more named slots you add to and recall. Use it for a running subtotal you keep coming back to.

Variables let you name a value and use the name in later expressions — assign r = 4.2 and then write pi * r^2. For any calculation with more than two steps this is far less error-prone than re-typing numbers, and it makes the tape readable afterwards.

The tape is the running record of everything you have calculated. It is the feature physical calculators lack and the reason accountants kept printing adding machines. Because each line is editable and everything downstream recalculates, you can correct an input from ten steps ago without redoing the work.

Parentheses and order of operations

The engine follows standard precedence: parentheses first, then exponents, then multiplication, division and modulo, then addition and subtraction, working left to right within each level. So 2 + 3 × 4 = 14 and (2 + 3) × 4 = 20.

Where precedence is genuinely ambiguous in everyday writing — expressions like 6 ÷ 2(1+2), which circulate online precisely because notation is unclear — the honest advice is not to memorise a rule but to add brackets. The bracket counter under the input tells you how many are still open, so long expressions do not become guesswork.

Common scientific calculator mistakes

  • Wrong angle mode. By a wide margin the most common. Check DEG/RAD/GRAD before trusting any trig answer.
  • Confusing log and ln. Here log is natural and log10 is base 10 — the opposite of the key labels on a physical calculator.
  • Missing brackets around a negative base. -3^2 is −9; (-3)^2 is 9.
  • Assuming percentages chain. A 10% rise followed by a 10% fall does not return you to the start — it leaves you at 99%.
  • Rounding too early. Round once, at the end. Rounding intermediate steps compounds the error.
  • Trusting the last digits. Double precision gives about 15 significant digits; anything beyond that is noise.

For students, engineers and physicists

Students mostly need trigonometry in degrees, logarithms, powers and roots, and reliable order of operations. The tape is unusually useful for homework because it shows your working — you can read back the steps you took rather than re-deriving them.

Engineers benefit most from the unit-aware arithmetic and base conversion. You can write 5 km + 300 m and get a sensible answer, or flip a value between decimal, hexadecimal, octal and binary with the bitwise operators alongside. For repeated financial calculations, our EMI calculator handles amortisation properly rather than making you rebuild it from a formula.

Physicists and chemists want scientific notation that behaves, constants that are correct, and radians available in one tap. Combine variables with the tape and a multi-step derivation stays auditable.

Scientific vs basic vs physical calculators

Calculator types compared
FeatureBasic calculatorThis calculatorPhysical scientific calculator
Order of operationsOften left to rightFull precedenceFull precedence
Trig and logsNoYesYes
Editable historyNoYes, recalculating tapeLimited replay at best
Named variablesNoYesA few lettered stores
Copy and pasteNoYesNo
Allowed in examsSometimesNoOften, if an approved model
Works without powerBatteryNeeds a deviceSolar or battery, years

The honest summary: a browser calculator wins on history, variables, copy-paste and never being in the other room. A physical calculator wins on exam rooms and battery life. Neither replaces the other.

Keyboard shortcuts

Keyboard shortcuts
KeyAction
0–9 . ( )Type directly into the expression
+ − * /Operators
^Power
EnterEvaluate and push to the tape
BackspaceDelete the character before the cursor
EscapeClear the expression
← →Move the cursor within the expression
Home / EndJump to the start or end

Because the expression is an ordinary text field, everything you expect from a text field works — select, copy, paste, and edit in the middle rather than deleting back to your mistake.

Privacy

Every expression is parsed and evaluated in your browser. There is no server component, so your calculations, tape, variables and memory are never transmitted — they are held in memory and, where you have used a feature that persists, in your browser's local storage on this device only.

You can verify it in about ten seconds: open developer tools, switch to the Network tab, and run a few calculations. You will see the page's own files and the maths engine load once, and nothing after that. The engine is currently fetched from a public CDN, which reveals that a file was requested but never what you typed; self-hosting it to remove even that request is on our list. Full details are in our privacy policy.

For everyday percentage work — discounts, tax, tips, percentage change — the dedicated percentage calculator is quicker than typing the formula each time. Converting between units of length, mass, temperature or area is cleaner in the unit converter than as an expression. If you are working out how old something is or counting days between dates, the age calculator handles the calendar edge cases. For loan repayments use the EMI calculator, and for course marks the GPA and CGPA calculator. When you need unpredictable numbers rather than computed ones, the random name picker is the tool for drawing lots.

Frequently asked questions

What is a scientific calculator?

A calculator that understands mathematical structure rather than just a sequence of keypresses. It applies correct order of operations, handles parentheses, and adds trigonometry, logarithms, exponents, roots, factorials and scientific notation. The defining test: type 2 + 3 × 4. A scientific calculator answers 14; a basic one often answers 20.

Is this scientific calculator free?

Yes, completely. No account, no trial, no paid tier, no limit on calculations, and no watermark on anything you copy out.

Does it work on mobile?

Yes. The layout collapses to a single column, the keypad drops to four columns with full-size keys, and the display scales with the viewport. You can also use your phone's own keyboard to type expressions directly.

Does it require a download?

No. It is a web page. You can optionally add it to your home screen to open it like an app and use it without a connection.

Does it support sin, cos and tan?

Yes, along with their inverses (asin, acos, atan), the hyperbolic versions (sinh, cosh, tanh) and the inverse hyperbolics. All of them respect the DEG, RAD or GRAD setting you have selected.

What is DEG mode?

Degrees, where a full circle is 360. It is what school geometry, surveying and most engineering drawings use. In DEG mode sin(30) equals 0.5.

What is RAD mode?

Radians, where a full circle is 2π ≈ 6.283. It is the natural unit for calculus and physics, because the derivative of sin(x) is cos(x) only when x is in radians. In RAD mode sin(pi/2) equals 1.

What is GRAD mode?

Gradians, where a full circle is 400 and a right angle is exactly 100. It appears mainly in some European surveying and civil engineering traditions. In GRAD mode sin(100) equals 1.

How do I calculate a factorial?

Type the number followed by an exclamation mark: 6! gives 720. Factorials are defined for non-negative whole numbers, and 0! is 1 by definition. They grow extremely fast — 20! is already about 2.4 × 10¹⁸.

How do I calculate square roots?

Use sqrt(144) for 12, cbrt(27) for cube roots, or nthRoot(32, 5) for any other root. A root is just a fractional power, so x^(1/2) gives the same answer as sqrt(x).

How do I calculate powers?

Use the caret: 2^10 gives 1024. Note two conventions — exponents bind tighter than a leading minus, so -2^2 is −4 and you need (-2)^2 for 4; and exponentiation is right-associative, so 2^3^2 is 2^9 = 512 rather than 64.

What is ln?

The natural logarithm, base e ≈ 2.71828. It answers "what power of e gives this number?", so ln(e) = 1. It appears wherever something grows or decays in proportion to its own size. In this calculator type it as log(x) — see the next answer.

What is the difference between log and ln?

In this engine log(x) is the natural logarithm and log10(x) is base 10, which is the programming-library convention and the opposite of the key labels on a physical Casio or TI. If a logarithm looks wrong by a factor of about 2.303 — which is ln(10) — this is why. For any other base, log(x, b) works directly.

What is scientific notation?

Writing a number as a value between 1 and 10 times a power of ten, such as 6.022 × 10²³. Type it as 6.022e23. The display switches to it automatically above 10¹⁵ and below 10⁻⁹, where the plain digit string stops being readable.

Can I use keyboard shortcuts?

Yes, and it is the fastest way to use it. Type the whole expression as text; Enter evaluates, Escape clears, Backspace deletes, and the arrow keys, Home and End move the cursor. Because the input is an ordinary text field, select, copy and paste all work as usual.

Does it keep a calculation history?

Yes — a running tape. Every calculation is recorded with its expression and result. Click a past result to insert it into the current expression, or edit a past line and everything after it recalculates in order. That last part is what physical calculators cannot do.

Does it have memory functions?

Yes, plus named variables. Memory is the classic store-and-recall behaviour for a running subtotal. Variables let you name a value — assign r = 4.2 and then write pi * r^2 — which is far less error-prone for multi-step work and makes the tape readable afterwards.

Can I copy results?

Yes. The result and any tape entry can be copied, and because the expression field is standard text you can select and copy from it directly with the keyboard.

Does it work offline?

Yes, after your first visit. A service worker caches the page and the maths engine, so it opens and calculates with no connection — including your tape, memory and variables, which live on your device.

Are calculations sent to a server?

No. Expressions are parsed and evaluated entirely in your browser; there is no server component to send them to. Open developer tools, go to the Network tab and run some calculations — you will see the page's files and the maths engine load once and nothing afterwards.

Does it use eval()?

No. Expressions are tokenised and evaluated by a dedicated maths library with its own parser. That matters for accuracy — it applies real operator precedence — and for security, since nothing you type into the field can execute as code.

Why does 0.1 + 0.2 not give exactly 0.3 on some calculators?

Because computers store numbers in binary and some decimal fractions have no exact binary form, the same way 1/3 has no exact decimal form. The raw result is 0.30000000000000004. This calculator rounds at the display layer, so you see 0.3, while the underlying value keeps full precision so errors do not accumulate through a chain of calculations.

How precise is it?

It uses standard double-precision floating point, giving about 15 to 17 significant decimal digits. That is comfortably enough for engineering, physics and school mathematics. It is not arbitrary precision — if you need fifty digits of π, this is the wrong instrument.

Is it useful for engineering?

Yes, particularly the unit-aware arithmetic — you can write 5 km + 300 m and get a sensible answer — plus base conversion between decimal, hex, octal and binary with bitwise operators, matrices, and an equation solver.

Is it useful for physics?

Yes. Scientific notation, correct constants, one-tap radians, and named variables that keep a multi-step derivation auditable on the tape rather than living in your head.

Can I use it for school mathematics?

Yes, and the tape is genuinely useful for homework because it shows your working. One caveat: it is a browser tool, so it will not be permitted in an exam room where an approved physical model is required. Check your exam board's rules.

Why does my trig answer look wrong?

Almost always the angle mode. sin(30) is 0.5 in DEG but about −0.988 in RAD, because 30 radians is a completely different angle. Neither is an error; only one answers the question you meant. Check the DEG/RAD/GRAD indicator at the top left before trusting any trigonometric result.

How do I calculate percentages?

Use the dedicated percentage buttons to avoid ambiguity: "200 + 10%" correctly gives 220 — ten percent of 200 added on — rather than 200.1. There are also direct buttons for "what % is A of B" and "A is B% of what". For heavier percentage work, the dedicated percentage calculator is quicker.

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