Scientific Calculator

About this calculator

This scientific calculator supports standard arithmetic (+, -, x, /), percentage, parentheses, square root, squaring, sine, cosine, tangent (in degrees), natural logarithm (ln), base-10 logarithm (log), and the constant pi. All computation runs in your browser.

How do I use a scientific calculator's order of operations?

A scientific calculator evaluates parentheses first, then exponents and functions (sqrt, sin, cos, tan, ln, log), then multiplication and division left to right, then addition and subtraction left to right. Example: 2 + 3 x 4 = 14 (multiplication before addition), while (2 + 3) x 4 = 20 (parentheses override the default order).

Steps to evaluate an expression

1. Enter numbers and operators (+, -, x, /) in the order you would write the expression on paper, using parentheses to group any part that should be calculated first.
2. Trigonometric buttons (sin, cos, tan) evaluate the current expression's value in degrees, not radians, and immediately replace the display with the result.
3. sqrt and x2 (square) apply to whatever value the expression currently evaluates to, replacing the display with the new value.
4. ln applies the natural logarithm (base e) and log applies the base-10 logarithm to the current value; both require a positive number.
5. Press = to evaluate the full expression respecting standard order of operations, or press C at any point to clear and start over.

Standard order of operations (PEMDAS)

• sin, cos, tan = trigonometric functions evaluated in degrees
• ln = natural logarithm (base e) | log = common logarithm (base 10)
• pi (π) inserts the constant 3.14159265358979...

Example calculations

Frequently asked questions

Why does 2 + 3 x 4 equal 14 and not 20?

Standard math notation evaluates multiplication and division before addition and subtraction, regardless of the order they are typed in. So 3 x 4 is calculated first (giving 12), then 2 is added, giving 14. Wrapping 2 + 3 in parentheses forces that part to be calculated first instead, giving (2+3) x 4 = 20.

Are the trigonometric functions in degrees or radians?

This calculator uses degrees, the everyday unit where a full circle is 360 degrees, rather than radians (where a full circle is 2π). sin(30) returns 0.5, matching the standard 30-degree angle result, not the very different result you would get by treating 30 as radians.

Why do sqrt and the trig functions apply to the whole expression instead of just the last number?

These function buttons evaluate whatever the current expression works out to at the moment you press them, similar to a physical scientific calculator, rather than wrapping only the most recent digit. If you type 9 + 7 and then press sqrt, it takes the square root of 16 (9+7), not just of 7.

Why does log or ln show nothing for negative numbers or zero?

Logarithms are mathematically undefined for zero and negative numbers — there is no real exponent that produces a non-positive result from a positive base. The calculator only computes log and ln when the current value is greater than zero.

This calculator evaluates one expression at a time using standard order of operations and degree-based trigonometry; it does not support memory storage, radians mode, or multi-variable equations, and very large results may lose precision beyond about 15 significant digits due to standard floating-point arithmetic.

Privacy and safety

• Runs in your browser — Everything you type is calculated on your own device. Your inputs are never sent to a utilduck server.
• Encrypted connection — Pages are served over HTTPS, so nobody on the network can read what you load.
• Not shared with third parties — Your inputs are not passed to analytics or advertising services.
• Nothing is stored — Results are not saved to any server, and there is no account to create.

Last updated: 2026-08-17