Online scientific calculator, with multi-line calculations

This free online scientific calculator works the way the Calculate application of a TI-Nspire CX does: you write out a whole calculation on one line, press Enter, and it stacks on top of the previous one.

The screen therefore keeps your entire train of work, instead of showing a single number the way an ordinary calculator does.

It is not a graphing calculator: it does not draw curves (that is the job of the site’s graphing calculator). It is built for numeric work — trigonometry, logarithms, powers, roots, factorials, degrees-minutes-seconds, sums and products of sequences, numeric derivatives, integrals, equation solving, statistics and variables — with the order of operations respected and parentheses handled at any depth.

For plain arithmetic, the site’s basic online calculator, with its large keys and single display, is often quicker.

Help for the scientific calculator

Writing a calculation on several lines

It works like a worksheet: every line you enter stays on screen with its answer, aligned to the right. You can read your whole method back — and, more importantly, reuse it.

Click a calculation you already entered to put it back on the entry line and correct it. Click an answer to insert it at the cursor in the calculation you are writing. The ↑ and ↓ keys scroll through previous entries, exactly like the entry recall of a TI calculator.

The word ans always means the last answer: after 2+3, typing ans×4 gives 20. It is the shortest way to keep going without copying a number back down.

Finally, the : character puts several calculations on the same line: 5→a : a²+1 stores 5 in a and then shows 26, on two separate screen lines. It has its own key on the keypad, to the right of the catalog.

Accepted operations and notation

Basic operations

The four operations are written +, -, × (or *) and ÷ (or /). The order of operations is respected: 2+3×4 is 14, not 20.

Powers use ^: 2^10 is 1024. They associate to the right, so 2^3^2 is 2⁹, that is 512, just like on a TI.

Implied multiplication

The multiplication sign may be left out in front of a parenthesis, a constant or a function: 2(3+4), 2π and 3sin(30) are all understood.

Two letters written side by side, on the other hand, name a single variable: to multiply a by b, write a×b.

Suffixes

After a number you may write ! for the factorial (5! = 120), % for a percentage (50% = 0.5), ² and ³ for the square and the cube, ⁻¹ for the reciprocal, and ° to mark an angle in degrees even when the calculator is working in radians.

The period and the comma

The decimal separator is the period: write 1.5, never 1,5.

The comma has two other jobs, and the calculator tells them apart on its own. Inside the parentheses of a function it separates the arguments: in log(8,2) the comma separates the number from its base, and the answer is 3. Outside a function call it is read as a thousands separator, so a figure pasted straight out of a word problem or a statement behaves as you expect: 1,250,000÷8 gives 156250.

A comma placed anywhere else — 1,5, for instance — is reported as an error rather than quietly turned into something else.

Unclosed parentheses

Parentheses left open are closed for you when the line is computed: sin(30 is accepted and gives the same answer as sin(30).

Degrees, radians or gradians

The angle mode is chosen at the top of the calculator and stays visible to the right of the entry line (DEG, RAD or GRA). It is the setting that most often looks like a calculation error: sin(30) is 0.5 in degrees, but −0.988 in radians.

The default is degrees, the mode used throughout geometry and trigonometry in middle school and high school. The ° suffix forces degrees without changing the mode: in radian mode, sin(30°) still gives 0.5.

Inverse functions follow the same setting: in degrees, asin(0.5) returns 30; in radians, it returns 0.523598775598.

Angles in degrees, minutes and seconds

One degree is divided into 60 arcminutes, written ′, and one minute into 60 arcseconds, written ″. This is the notation of surveying, of latitude and longitude, and of astronomy.

You can type it as it stands: 12°30′45″ is read as one block and equals 12.5125 degrees. Minutes and seconds may be left out, and either may be used on its own (30′ is half a degree).

On a computer keyboard the plain apostrophe and quotation mark will do; on the calculator keypad, 2nd then ( gives the minute, and 2nd then ) the second.

The other way round, dms( writes a decimal angle in that form: dms(12.5125) returns 12°30′45″. The angle is read in the unit chosen at the top of the calculator, so dms(π/6) in radian mode correctly gives 30°0′0″.

The result of dms( is a notation, not a number: it cannot be used in another calculation, and the calculator says so if you try. To keep going, start again from the decimal value.

Exact answers: fractions, π and roots

Whenever a decimal answer matches a simple exact form, that form is recognised and shown underneath: 0.1+0.2 shows = 3/10, √2 shows = √2, and π/4 stays π/4. The Exact button swaps them round: the exact form moves to the large line, the decimal value to the small one, preceded by ≈.

Fractions are searched up to a denominator of 10,000, multiples of π up to a denominator of 100, and square roots of whole numbers up to 1,000,000. This is not computer algebra: the exact form is recognised from the decimal answer, with a tolerance strict enough that no irrational number is ever mistaken for a fraction.

Variables

An answer can be stored under a name, exactly as on a TI, using the arrow →: 12→a puts 12 in a. Writing a:=12 does the same thing. A name starts with a letter and is at most sixteen characters long. Upper and lower case are not distinguished.

Stored variables appear under the screen with their values. Clicking one inserts it into the calculation you are writing. The Clear all button deletes them all.

To write a name without using the computer keyboard, the abc key replaces the function block with the twenty-six letters. It stays visible until you go back to the functions, so a multi-letter name can be typed in one go, and the digits and the Enter key stay available meanwhile.

The names e, pi, π, ans and the function names are reserved and cannot be used as variables.

Lists and statistics

A list of values is written between braces: {1,2,3}. Operations apply term by term ({1,2,3}×2 gives {2, 4, 6}) and so do single-argument functions: sin({0,30}) gives {0, 0.5} in degree mode.

Statistical functions accept either a list or several arguments: mean({1,2,3,4}) and mean(1,2,3,4) both give 2.5.

You have mean, median, sum, product, min, max, count, variance, stDevSamp and stDevPop (sample or population standard deviation).

On the calculator keypad the opening brace can be reached three ways: 2nd then the , key; the New list entry in the catalog; or the letters layer, where it has its own key. The closing brace has its own key right beside it on that layer, and the catalog entry Close the list does the same without leaving the function block. It is only needed in the middle of a calculation, as in {1,2}+{3,4}: at the end of a line it is added for you when the line is computed, just like parentheses, and {1,2,3 is enough.

For an average weighted by coefficients, the weighted average calculator is more direct. For a plain average, see the average calculator.

Sums, products, derivatives, integrals and equations

These five functions have one thing in common: their first argument is not a number but an expression containing a variable, which the calculator evaluates as many times as it needs to. You therefore always give the name of that variable straight after the expression.

Sum and product of a sequence

Σ(expression, variable, start, end) adds the terms for the variable running from start to end, both whole numbers. Σ(k²,k,1,10) gives 385, the sum of the squares from 1 to 10. Π( does the same with products: Π(k,k,1,5) is 120. If the end is below the start, the sum is 0 and the product is 1, by convention. The total is capped at 100,000 terms.

Numeric derivative

nDeriv(expression, variable, point) gives the slope of the curve at that point: nDeriv(x²,x,3) is 6. The calculation is numeric — the calculator compares values either side of the point, it does not find the derivative as a formula. The answer is given to ten significant digits instead of twelve, because that method does not guarantee more.

Integral

nInt(expression, variable, a, b) computes the area under the curve between the bounds a and b: nInt(x²,x,0,1) is one third. The method splits the interval into a thousand pieces and approximates the curve with parabolic arcs.

Solving an equation

nSolve(equation, unknown) looks for a value that makes the two sides equal: nSolve(x²=2,x) returns 1.41421356237. The = sign is used there and nowhere else; anywhere else the calculator reports a malformed expression.

The search sweeps the interval from −100 to 100 and returns the solution closest to zero. When an equation has several, a third argument steers the search: nSolve(x²=2,x,-1) returns −1.41421356237 instead. If nothing is found, the calculator says so rather than returning a wrong answer.

The working variable stays local: after Σ(k,k,1,10), the variable k gets its previous value back (or becomes undefined again if it had none).

The 2nd key and the catalog

The 2nd key reaches the second function printed on the keys: sin becomes sin⁻¹, ln becomes eˣ, x² becomes x³, n! becomes nCr. As on a TI, it applies to the next key only, then releases itself.

The Function catalog menu gathers every available function, sorted by family. That is where you will find the hyperbolic functions, rounding, modulo, gcd, statistics, random draws, degrees-minutes-seconds and the calculus functions (sum, product, derivative, integral and equation solving). Choosing an entry inserts it into the calculation, ready for its arguments. To its right, the : key chains several calculations on one line.

The abc key shows the letters, for naming a variable. They take the place of the function block, so the comma , and both braces { and } also appear on that layer, next to ← f(x): without them you would have to switch back to the functions at every separator. A calculation mixing a variable and arguments (Σ(k²,k,1,10), nSolve(x²=2,x) or a list {a,b}) can therefore be typed in one go. Unlike 2nd, the letters layer does not release itself after one key: it stays until you press ← f(x).

Between the keypad itself, the 2nd key, the catalog and the letters, everything the calculator can do is reachable with a mouse or a finger: the computer keyboard only saves time, it does not unlock anything extra.

Every notation, one by one

The table below gathers everything the calculator can read: the operators, the suffixes, the constants and some fifty functions, each with what it does and an example together with its answer. The contents list at the top of this help leads straight to any section.

Examples are given in degree mode unless stated otherwise. Spelled-out English names (average, squareroot, absolute, modulus, remainder, random, stdev, deriv, integral, solve) are accepted alongside the original ones.

Equivalent notations

Several signs lead to the same result: a computer keyboard has no × or ÷ key, and many functions have a spelled-out name beside their original one. Every notation below is accepted and gives exactly the same calculation as the one on the right.

This is not a list of shortcuts to memorise: it is what the calculator tolerates if you write it that way without thinking. When in doubt, the notation on the right is always correct.

How numbers are displayed

Three settings are offered. Automatic shows the number as it is, rounded to twelve significant digits, and switches to scientific notation beyond 10¹² or below 10⁻⁶. Fixed decimals forces a number of digits after the point, from 0 to 12 (handy for money). Scientific writes every answer as a mantissa followed by a power of ten.

Changing the setting reformats the whole screen, including calculations already done: the values are kept, only their appearance changes. Nothing is recomputed, and no precision is lost along the way.

Scientific notation is typed with the ᴇ key: 1.5ᴇ3 is 1500. The forms 1.5E3 and 1.5e3 are accepted too.

Using the computer keyboard

Everything can be typed straight in: digits, operators, parentheses and function names. If the cursor is not on the entry line, the first key you press brings it back there (so there is never any need to click first).

Examples

For 2×3, type 2*3 and Enter. For the sine of 30°, type sin(30) and Enter. For the square root of 2, type sqrt(2) and Enter. For 2 to the power 5, type 2^5 and Enter.

A few useful keys

Enter ⇝ compute the line

⌫ ⇝ delete the previous character

↑ ⇝ previous calculation

↓ ⇝ next calculation

* ⇝ ×

/ ⇝ ÷

^ ⇝ power

( ) ⇝ parentheses

The results history

Every calculation you enter is also recorded in the “Results history” table below the calculator, with the expression and its answer. Every cell there can be edited, and a notes column lets you annotate rows.

You can export that table as CSV to open it in a spreadsheet, or generate a PDF document.

Saving your calculations as an image, or sharing them

Under the keypad, two buttons act on the whole screen.

Save image produces a PNG file of the entire screen: every calculation with its answer, the exact form where there is one, the stored variables and a reminder of the settings (angle mode, display, number of decimals).

The image is produced at twice the size of the screen. It therefore stays sharp when you paste it into homework, a lab report or a slide deck, and when you print it. It always comes out on a light background.

Share link builds an address that contains the whole screen: the calculations, their answers, the variables and the settings. Whoever opens it gets exactly the same screen back, and can keep calculating from there.

The link is copied to your clipboard, ready to paste into a message. If your browser refuses the automatic copy, it appears in a field just below, already selected. Nothing is stored on the site: everything is held in the address, and no account is needed. Since an address cannot grow indefinitely without being cut in half by messaging apps, only the last fifty calculations go into it (fewer if they are very long, and you are told when that happens).

Opening a link you received does not touch your own calculations: if you had switched “Keep my calculations” on, this device’s memory is simply paused for that visit, and you get your calculations back the next time you load the page without the link.

Keeping your calculations from one visit to the next

The screen starts empty on every visit. The “Keep my calculations” switch, at the bottom of the calculator, changes that: the last fifty calculations on screen are then saved in your browser, along with your variables, the last answer and your angle and display settings. You get them back exactly as they were on your next visit, even after closing the tab.

Nothing is sent over the internet: everything stays in this browser, on this device (so your calculations do not follow you from one computer to another).

The switch is off to begin with, because on a shared machine — a school library or a classroom — finding the previous visitor’s calculations would not be pleasant. Switching it off erases at once whatever had been kept, and the C key clears the screen and that memory alike.

Scientific calculator or graphing calculator?

A scientific calculator does numeric work: it returns a number. A graphing calculator adds curve plotting, function study and often a spreadsheet. The TI-Nspire CX and the TI-84 Plus CE belong to the second family, but their Calculate screen — the one reproduced here — is a scientific calculator, and it is the one you use most of the time.

This page therefore covers the calculations, not the plots: to draw a curve and read off its zeros, extrema and tangents, go to the online graphing calculator. To solve an equation exactly, see the quadratic equation solver or the linear equation solver. For scientific notation on its own, see the scientific notation converter.

Who it is for

Middle school and high school students, to check a trigonometry or power calculation without digging out their calculator. College students, for a logarithm, a standard deviation or a quick count. Teachers, who can project the screen and show a chain of calculations that stays readable.

And anyone who, faced with a long calculation, would rather write it out in full and read it back than press key after key and hope nothing went wrong on the way.