A scientific calculator extends the four basic operations with the functions that appear throughout mathematics, physics and engineering: trigonometry, logarithms, exponents and factorials. Everything here runs locally — no account, no limits, nothing recorded.
How to use the Scientific Calculator
- Enter numbers with the keypad or your keyboard
- Use the function buttons for trigonometry, logarithms, powers and roots
- Check whether you need degrees or radians before using sin, cos or tan
- Press = to evaluate
The functions and what they are for
- sin, cos, tan — trigonometric ratios. Essential for anything involving angles, waves or rotation.
- log — base-10 logarithm. The scale behind decibels, pH and the Richter scale.
- ln — natural logarithm, base e. Appears wherever growth or decay is continuous: compound interest, radioactive decay, population models.
- √ and x² — roots and squares. Pythagoras, standard deviation, areas.
- xʸ — arbitrary powers, for compound growth and scaling.
- n! — factorial, the basis of permutations and combinations.
- π and e — the two constants you cannot avoid.
Degrees and radians, and the mistake everyone makes
Trigonometric functions can take their input in either unit, and getting it wrong produces an answer that looks plausible and is completely wrong.
Degrees divide a circle into 360 parts. This is what most practical problems — construction, navigation, geometry homework — are stated in.
Radians measure the angle as arc length over radius, so a full circle is 2π. This is the mathematically natural unit and what calculus, physics and every programming language's standard library assume.
The conversion is radians = degrees × π / 180. If sin(90) gives you 0.894 rather than 1, the calculator is in radian mode — 90 radians is about 14 full rotations. Check the mode before trusting a trigonometric result.
Frequently asked questions
Why does sin(90) not give me 1?
The calculator is working in radians. 90 radians is roughly 14 full rotations, so the result is unrelated to the 90° you intended. Convert with degrees × π / 180, or switch the mode.
What is the difference between log and ln?
log is base 10 — it answers 'ten to what power gives this'. ln is base e (≈2.718) and appears wherever change is continuous, such as compound interest or radioactive decay.
How large a factorial can it calculate?
Up to 170!. Beyond that the result exceeds the largest number JavaScript can represent and returns Infinity. For larger values you need arbitrary-precision arithmetic.
Is my calculation history stored anywhere?
No. Everything runs in your browser and nothing is transmitted or saved to a server.
Can I use my keyboard?
Yes — number keys and the basic operators work as expected, with Enter to evaluate.