Scientific Calculator
Full-featured scientific calculator with trig, log, power, and more.
How to Use
- Step 1: Click number buttons to enter a value.
- Step 2: Press an operator (+, −, ×, ÷) then enter the second number.
- Step 3: Press = to compute the result. For functions (sin, log, etc.), enter the number first then press the function button.
- Step 4: Press C to clear all, or CE to clear only the current entry.
About Scientific Calculator
This free online scientific calculator provides all the functions you need for academic, engineering, and everyday math. Unlike basic calculators, it includes trigonometric functions (sin, cos, tan in degrees), logarithms (base-10 log and natural log), square root, squaring, and arbitrary power (xⁿ). Mathematical constants π and e are also available.
The calculator uses chained operations: enter a value, press an operator, enter the next value, and press = to compute. Functions like sin, cos, sqrt, and log apply immediately to the displayed value without needing to press =. The expression bar at the top shows the current calculation context.
All computation is done entirely in your browser using JavaScript's built-in Math library. No data is sent to any server, making it completely private. The interface is designed to be intuitive on both desktop and mobile.
You may also find our Fraction Calculator and Quadratic Solver helpful.
Frequently Asked Questions
Does this calculator use eval()?
No. All operations are computed using direct Math functions, making it safe and secure.
Are trigonometric functions in degrees or radians?
The trig functions (sin, cos, tan) operate in degrees for user convenience.
What is the maximum precision?
JavaScript numbers are IEEE 754 double-precision floats, giving about 15 significant digits.
How does xⁿ work?
Enter the base, press xⁿ, then enter the exponent and press =.
Is my calculation history saved?
No. The calculator is session-only and nothing is stored or transmitted.
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Guide
How to use the scientific calculator for trig, logs and powers
This is an on-screen scientific calculator with a four-column button grid. Along with the digits and the four arithmetic operators it has sin, cos, tan, log, ln, a square root key, x² and a general power key xⁿ, plus the constants π and e, a sign changer, a percent key and two clear keys. A small line above the display shows the pending operation, and a Copy button next to the display copies whatever number is showing.
It works like a pocket calculator, not a formula editor. Function keys act on the number on screen straight away, and arithmetic is chained in the order you press it. Knowing those two rules prevents nearly all surprises. Trigonometric keys work in degrees only.
Step by step
- Press digit keys and the decimal point to enter a number. A second decimal point in the same number is ignored.
- For a function such as sin, cos, tan, log, ln, √ or x², enter the number first and then press the function key. The answer replaces the display immediately.
- For arithmetic, press an operator (÷, ×, −, +), enter the second number, then press = to see the result. The line above the display records what you did.
- For powers, enter the base, press xⁿ, enter the exponent and press =. The key π or e inserts the constant.
- Press CE to clear only the number you are typing, C to wipe everything, ± to change the sign, and Copy to take the result away.
When this is useful
- Checking physics or maths homework that uses angles in degrees.
- Finding the height of a tower, a ramp or a roof from a distance and an angle.
- Working out logarithms, for example the pH of a solution from a concentration.
- Squaring, rooting and raising numbers to powers during quick estimates.
Worked example: Height of a building from distance and angle
From a spot 40 m from the foot of a building, the angle to the top is 35°. Press 3, 5, then tan, and the display shows 0.7002075382. Press ×, 4, 0, then =, and the answer is 28.008301528, so the building is about 28 m above eye level. Add the eye height of the observer to get the full height. The same chain works in any order as long as the first number is entered before the function key.
Tips for better results
- Press = after a function key before you press the next operator, so the pending sum is kept.
- Break a long expression into pieces and note intermediate results, because there is no bracket support.
- Use the % key for dividing by 100, as in 10 then % to get 0.1.
- The display holds up to about 12 significant digits, and very large results appear in exponent form like 1e+22.
Common mistakes
- Expecting normal order of operations. Entries are applied left to right, so 2 + 3 × 4 gives 20, not 14. Work out the multiplication first and enter the sum in the right order.
- Changing your mind about an operator. Pressing + and then × computes the pending step with the same number, so 5 + × shows 10. Use C and start again if you press the wrong operator.
- Pressing an operator straight after a function. Entering 2 + 9 √ + 1 = gives 4 because the pending 2 + is dropped, while 2 + 9 √ = + 1 = gives 6.
- Using the ( key. It is on the keypad but does nothing, and there is no closing bracket key.
- Reading tiny remnants as real answers. sin 180 shows 1.224646799e-16 rather than 0, and cos 90 shows 6.123233996e-17, because of floating-point rounding. Treat them as zero.
Your files and privacy
Every calculation runs in your browser using built-in maths functions, with no formula sent to a server and nothing saved. There is no history list, and numbers clear when you leave or reload the page. The Copy button only writes the display to your clipboard.
Frequently asked questions
Are the angles in degrees or radians?
Degrees. The sin, cos and tan keys convert your number from degrees internally, and there is no switch for radians. To use a radian value, multiply it by 180 and divide by π first.
Does it follow BODMAS or PEMDAS?
No. Operations are carried out in the order you enter them, left to right. Do multiplication and division yourself first, or press = after each step to keep control.
What do log and ln mean?
log is the base-10 logarithm, so log of 1000 is 3. ln is the natural logarithm, with base e, so ln of e is 1. A zero or negative input shows Error.
What does the % key do?
It divides the displayed number by 100. It does not work out a percentage of another number, so 200 + 10 % = gives 200.1. For that, use a percentage calculator.
Why does it say Error?
Error appears when a result is not a real finite number, for example dividing by zero, taking the square root of a negative number, or the log of zero or a negative number.
Guide reviewed 2026-10-11 by the useToolify team.