Calculator

Calculator

A fast, free online calculator with basic and scientific modes, full keyboard support, order of operations, and a running history.

Tip: use your keyboard — digits, + − * / ^ ( ), Enter to evaluate, Esc to clear.

Last updated: March 2026Reviewed by CalculWise editorial team

Sources: MDN: JavaScript Math reference·Khan Academy: Order of operations

Methodology: Expressions are parsed into tokens, converted to Reverse Polish Notation with the shunting-yard algorithm, and evaluated in-browser. No eval() is used, and results are rounded to remove floating-point noise.

A free online calculator that just works

Sometimes you do not need a specialized tool — you just need a reliable calculator. This one handles everything from a quick tip-split to a chained scientific expression, runs entirely in your browser, and never asks you to sign up or install anything. Type with your keyboard or tap the buttons; the result updates live as you go.

Basic vs. Scientific mode

Basic mode covers the four core operations (addition, subtraction, multiplication, division) plus percent and parentheses — ideal for budgeting, shopping math, splitting a bill, or any everyday arithmetic.

Scientific mode adds the functions you need for algebra, trigonometry, statistics, and physics: sine, cosine and tangent (and their inverses), natural and base-10 logarithms, square roots, exponents, factorials, and the constants π and e. A DEG/RAD switch lets you pick the right angle unit for trigonometric work.

Order of operations, done right

The calculator follows standard order of operations (PEMDAS / BODMAS): expressions inside parentheses are evaluated first, then exponents, then multiplication and division from left to right, and finally addition and subtraction. So 2 + 3 × 4 returns 14, not 20. When you want a different grouping, add parentheses: (2 + 3) × 4 returns 20.

Keyboard shortcuts

0–9 and . — enter numbers
+ − * / ^ — operators (use ^ for powers)
( ) — parentheses for grouping
Enter or = — evaluate
Backspace — delete the last character
Escape — clear everything

Calculation history

Every result is saved to a short history list below the keypad. Tap any past result to drop it straight back into the display and keep working — handy when one answer feeds into the next step. History stays on your device and clears when you close the tab or hit Clear.

Privacy by design

All math happens locally in your browser. Nothing you type is transmitted, logged, or stored on a server, which makes this a safe choice for sensitive numbers like salaries, invoices, or account balances.

Frequently Asked Questions

Is this online calculator free to use?

Yes. The CalculWise calculator is 100% free, works in any modern browser, and requires no signup or download. It runs entirely on your device, so nothing you type is sent to a server.

How do I use the scientific functions?

Switch to Scientific mode using the toggle at the top. You then get trigonometric functions (sin, cos, tan and their inverses), logarithms (ln and log), square roots, powers, factorials, the constants pi and e, and a DEG/RAD switch for angle units.

What is the difference between DEG and RAD?

DEG (degrees) and RAD (radians) are two ways to measure angles. A full circle is 360 degrees or 2*pi radians. Trigonometric functions return different values depending on the mode, so set it to match your problem before calculating sin, cos, or tan.

Can I use my keyboard instead of clicking buttons?

Yes. Type digits and the operators + - * / ^ ( ) directly. Press Enter or = to evaluate, Backspace to delete the last character, and Escape to clear everything.

Does the calculator follow order of operations?

Yes. It follows standard mathematical order of operations (PEMDAS/BODMAS): parentheses first, then exponents, then multiplication and division, then addition and subtraction. Use parentheses to control grouping when in doubt.

How accurate are the results?

Calculations use the browser's double-precision floating-point arithmetic and are rounded to remove tiny rounding artifacts. For everyday math, finance, and science homework this is accurate to about 10 significant digits.