Scientific Calculator

This online scientific calculator runs every operation in your browser, so results appear the moment you press =. It handles the functions a basic calculator cannot: trig (sin, cos, tan), inverse trig via algebraic identities, natural and base-10 logarithms, arbitrary exponents, square roots, factorials, and the constants π and e. If you need a free scientific calculator online with sin, cos, tan, exponents, and memory keys, everything is on the keypad above.

1. Basic arithmetic. Use the digit keys 0 through 9 and the +, −, ×, ÷ buttons for addition, subtraction, multiplication, and division. Press = to evaluate. The top row of the display shows the full expression; the bottom line shows the current entry or the result.
2. Trig functions. Tap sin, cos, or tan and the calculator inserts the function plus an opening parenthesis. Type the angle, close the parenthesis, and press =. Example: sin(30) in DEG mode returns 0.5.
3. Mode toggle (DEG or RAD). The RAD/DEG button in the top-right of the keypad switches the angle unit. DEG treats your input as degrees; RAD treats it as radians. This only affects sin, cos, and tan. Check the mode before every trig calculation.
4. Logarithms and exponents. log is base 10, ln is the natural logarithm (base e). Use x^y to raise one number to another: 2^10 gives 1024. The √ button takes a square root, and π and e insert the constants directly.
5. Parentheses and order of operations. The calculator follows PEMDAS: parentheses, exponents, multiplication and division, addition and subtraction. Use ( and ) to group terms. 2 + 3 × 4 equals 14, but (2 + 3) × 4 equals 20.
6. Memory keys. MS stores the current display into memory. MR recalls the stored value into your expression. M+ adds the display to memory, M− subtracts it, and MC clears memory. Use memory to hold a sub-result while you compute another part of a longer calculation.
7. Clearing and editing. AC wipes the expression and display back to zero. The ⌫ (backspace) key removes the last character only, which is useful for fixing a typo without starting over.

Every evaluated expression is added to the Calculation History panel on the right so you can reread or double-check your work. The history holds the last ten entries and clears on page refresh.

A scientific calculator is a multi-tool, not a single-formula machine. Each key runs a specific math function. The sections below explain what every button on this calculator does, with worked examples you can type in directly to verify.

Trigonometric Functions: sin, cos, tan

The sin, cos, and tan keys compute the sine, cosine, and tangent of an angle. The result depends on whether the calculator is in DEG or RAD mode, so always check the toggle before pressing =.

DEG mode (angle in degrees):
sin(30)  = 0.5
cos(60)  = 0.5
tan(45)  = 1

RAD mode (angle in radians):
sin(π/6) = 0.5     (π/6 rad = 30°)
cos(π)   = −1
tan(π/4) = 1       (π/4 rad = 45°)

For inverse trig (asin, acos, atan) on this calculator, use the algebraic identity: if sin(x) = 0.5 and you want x, you already know it is 30° or π/6. For values not on the standard triangle, type the algebraic relationship, or use a scientific calculator with dedicated inverse buttons for problems that do not simplify.

Logarithms: log and ln

log computes the base-10 logarithm (common log). ln computes the natural logarithm, base e ≈ 2.71828. Logarithms answer the question, "what exponent turns the base into this number?"

log(1000)   = 3           (because 10³ = 1000)
log(100)    = 2
log(1)      = 0
ln(e)       = 1           (because e¹ = e)
ln(1)       = 0
ln(7.389)   ≈ 2           (because e² ≈ 7.389)

Chemistry uses log for pH (pH = −log[H⁺]). Finance and biology use ln for continuous growth and decay. To compute a log in any other base, use the change-of-base rule: log base b of x equals ln(x) ÷ ln(b). For example, log base 2 of 32 = ln(32) ÷ ln(2) = 5.

Exponents and Roots: x², x^y, √, ∛

The x^y button raises any number to any power. To square a number, type it and press x^y then 2. For a cube root, raise to the power of 1 ÷ 3.

2^10      = 1024
5^3       = 125
7^0.5     = 2.6458...      (equivalent to √7)
√144      = 12
144^(1/2) = 12              (same thing)
27^(1/3)  = 3               (cube root of 27)
81^(1/4)  = 3               (fourth root of 81)

Fractional exponents are the general way to do any root. The nth root of x is written x^(1/n). Negative exponents give reciprocals: 2^(−3) = 1 ÷ 8 = 0.125.

Factorial: n!

The n! button multiplies every positive integer from 1 up to n. By definition, 0! = 1. Factorials grow extremely fast, so results above 20! lose precision in standard floating-point math.

0!  = 1
1!  = 1
5!  = 120           (5 × 4 × 3 × 2 × 1)
7!  = 5040
10! = 3,628,800
13! = 6,227,020,800

Factorials are the backbone of combinatorics. The number of ways to arrange 8 books on a shelf is 8! = 40,320. The number of 5-card poker hands from a 52-card deck is 52! ÷ (47! × 5!) = 2,598,960.

Constants: π and e

π (pi) ≈ 3.14159265, the ratio of a circle's circumference to its diameter. Use it in geometry (area of a circle = π × r²) and anywhere waves or rotations appear. e ≈ 2.71828, the base of the natural exponential. Use it for compound interest, population growth, radioactive decay, and anything continuously compounding.

Order of Operations and Parentheses

PEMDAS (Parentheses, Exponents, Multiplication and Division, Addition and Subtraction) is the rule the calculator follows. Multiplication and division bind tighter than addition and subtraction. Exponents bind tighter than both.

Without parentheses:   2 + 3 × 4²   = 2 + 3 × 16  = 2 + 48 = 50
With parentheses:      (2 + 3) × 4² = 5 × 16       = 80
Nested parentheses:    ((2 + 3) × 4)² = (20)²      = 400

When a calculation mixes trig, logs, and fractions, wrap each piece in parentheses. It is almost always worth typing an extra set of brackets to be certain the calculator groups the expression the way you meant it.

Quick Button Reference

A scientific calculator sits between the basic calculator on your phone and a graphing calculator or symbolic tool like Wolfram Alpha. Knowing which one to reach for, and the pitfalls that trip up every first-year engineering student, saves a lot of wasted time.

Scientific vs Basic vs Graphing: Which Do You Actually Need?

A basic calculator handles four-function arithmetic and a percent key. It cannot do trig, logs, or exponents. A scientific calculator adds every button covered on this page: sin, cos, tan, log, ln, powers, roots, factorials, and constants. A graphing calculator adds plotting and, on the programmable models, variables, loops, and matrix operations. For visualizing functions or doing calculus step-by-step, Desmos and Wolfram Alpha beat any handheld calculator.

The DEG vs RAD Gotcha

The single most common mistake in engineering and physics coursework is evaluating a trig function in the wrong angle mode. In DEG mode, sin(90) = 1. In RAD mode, sin(90) ≈ 0.894, because 90 radians is roughly 14 full rotations past a meaningful angle. Calculus and physics formulas almost always assume radians. Geometry, surveying, and navigation almost always use degrees. Check the RAD/DEG indicator before every trig press, and be especially careful after you reset or reload the calculator.

A quick sanity check: sin(30°) should be 0.5. If you type sin(30) and see 0.988 or −0.988, you are in RAD mode and the calculator just took the sine of 30 radians instead.

Scientific Notation on the Display

When a result is too large or too small to fit, most calculators switch to scientific notation, usually shown as a number followed by E and an exponent. 1.5E10 means 1.5 × 10¹⁰ = 15,000,000,000. 3.2E−7 means 3.2 × 10⁻⁷ = 0.00000032. The switch typically kicks in above 10 digits or below 0.0000001. This is the standard way very large or very small physical quantities (Avogadro's number, electron mass, astronomical distances) are written.

6.022E23   = Avogadro's number ≈ 6.022 × 10²³ molecules per mole
9.11E−31   = electron mass ≈ 9.11 × 10⁻³¹ kilograms
1.496E11   = Earth–Sun distance ≈ 1.496 × 10¹¹ meters
−4.2E6     = −4,200,000

Real-World Calculations Students and Professionals Run

Below are the most common problems where a scientific calculator pulls its weight. Each uses a function covered on this page.

Memorizing three shortcuts cuts most calculator work in half: multiplying by 1.05^n for yearly compounding, using ln(2) ≈ 0.693 for half-lives, and remembering that sin(30°), sin(45°), and sin(60°) are 0.5, √2 ÷ 2, and √3 ÷ 2. With those in your head, a lot of problems never need a calculator in the first place.