Free Online Scientific Calculator

When Do You Need a Scientific Calculator?

Your phone or desktop has a basic calculator for simple arithmetic. But the moment you move into high school math, college courses, or professional engineering, you'll find yourself needing more power. That's where a scientific calculator becomes essential.

For Students: A basic calculator can't help with trigonometry (sin, cos, tan) for your geometry homework, logarithms (log, ln) for chemistry class, or calculus (∫, d/dx) for your physics exams. Our calculator online is designed to replace your physical device, giving you all these functions for free.

For Professionals: Engineers, scientists, and programmers constantly work with complex equations. Whether you're calculating a vector in degrees, finding an exponential decay, or working in different number bases, our tool provides the precision you need without pulling a physical calculator out of your desk.

Sometimes, however, you don't need all this power. If you just need to figure out a marks percentage, you can use our simple marks percentage calculator. If you need to convert measurements for a project, our unit converter is the right tool. This scientific calculator is for when the math itself gets complex.

Understanding Your Calculator: Degrees vs. Radians

One of the most common mistakes that leads to the wrong answer is having your calculator in the wrong "mode." Our tool lets you switch between Deg (Degrees) and Rad (Radians). What's the difference?

Degrees (Deg)

This is the mode you're most familiar with. It's based on the idea that a full circle is 360 degrees.

• A right angle is 90°.
• A straight line is 180°.

When to use it: For most geometry, trigonometry, architecture, or navigation problems.

Example: sin(90) in Degree mode will correctly give you 1.

Radians (Rad)

This mode is based on the mathematical constant Pi ($\pi$). A full circle is 2$\pi$ radians.

• A right angle is $\pi$/2 radians.
• A straight line is $\pi$ radians.

When to use it: This is the default for higher-level math. You must use Radians for all calculus (derivatives, integrals) and most physics problems.

Example: sin(90) in Radian mode will give you 0.89..., which is the wrong answer. The correct input would be sin($\pi$/2), which gives 1.

Pro Tip: If your trigonometry or calculus equations aren't giving you the expected answer, the first thing you should check is your Deg/Rad mode.

What Are Logarithms & Exponentials? (A Quick Guide)

This calculator has "log" and "ln" buttons, which are essential for any work involving exponential growth or decay. But what's the difference?

Logarithms (log)

The "log" button on a calculator almost always means "base 10" (log₁₀). It's a way of asking, "10 to what power gives me this number?"

Real-World Use: This is used in science and engineering to measure things that have a massive range. The Richter scale for earthquakes and the decibel (dB) scale for sound are both logarithmic. A 6.0 earthquake is 10 times more powerful than a 5.0, not just one unit more.

Example: log(100) = 2, because 10² = 100.

Natural Logarithms (ln)

The "ln" button is a "natural log," which uses a special number called "e" (Euler's number, ~2.718) as its base.

Real-World Use: This is the language of nature, science, and finance. It's used to calculate compound interest, population growth, and radioactive decay.

Example: If you want to know how long it will take for your money to double in an investment, you'll be using natural logs.

Exponentials (eˣ)

This is the opposite of "ln." It's a way of saying, "What is 'e' raised to this power?" It is the mathematical key to modeling any system that grows or shrinks in proportion to its current size.

A Central Hub for All Your Calculation Needs

While this free online scientific calculator is your powerhouse for complex math, we know that not every problem requires calculus. Sometimes you just need a simple, fast answer to a specific question.

That's why we've built a full suite of dedicated calculators, each one perfectly designed for its task. This page is the "pro" tool, but here are our other popular utilities:

• Age Calculator: Need to know your exact age in days, months, or even seconds? Or find the time between two dates? This is the tool for you.
• Marks Percentage Calculator: Perfect for students. Quickly find out your grade on a test, calculate your final course percentage, or see what score you need on the final to pass.
• Unit Converter: Stop guessing how many centimeters are in an inch. This tool provides instant conversions for length, weight, temperature, volume, and more.

Our philosophy is to provide the right tool for the right job, all for free and with 100% privacy.