Free Scientific Calculator
Scientific Calculator evaluates full typed expressions with trigonometry, logarithms, powers, roots and factorials, in degrees or radians, with memory keys, Ans and a reusable history. It computes with 64-digit decimal numbers through math.js and shows up to 15 significant digits, so 0.1 + 0.2 gives exactly 0.3. It works with real numbers only.
- Precision:
- 64-digit decimals, 15 shown
- Angles:
- Degrees or radians
- Logarithms:
- log (base 10), ln, log(x, b)
- Price:
- Free
- Runs:
- Locally, in your browser
- Uploads:
- None: files never leave your device
- Account:
- Not needed
Quick answers
How accurate is it?
Calculations use 64-digit decimal numbers, then the result is shown with up to 15 significant digits. That avoids classic errors like 0.1 + 0.2 = 0.30000000000000004.
Does log mean base 10?
Yes. log(x) is the base-10 logarithm, ln(x) the natural logarithm, log2(x) base 2, and log(x, b) any base b.
Processed on your device: your files are never uploaded. How it works
Network activity in this tab
What this page has requested since you opened the site in this tab. An upload is any request that sends data: POST, PUT, PATCH or a request with a body.
No uploads: nothing has been sent from this page.
No network requests yet.
To see every request, open your browser's developer tools (Network tab).
How to use the Scientific Calculator
- Type an expression with your keyboard or tap the keys, for example sin(30) + 2^10.
- Watch the live preview, then press = or Enter for the result.
- Switch between DEG and RAD, use the memory keys and Ans, and click a history line to reuse it.
Credits & open source
Built on open-source libraries. Thank you to the people who make these projects.
- Math.jsExpression parser and math library with big-number support. © Jos de Jong and contributors · Apache-2.0
Web platform APIs used: Keyboard Events, localStorage.
Full license texts: third-party notices · all credits
Frequently asked questions
Can I use the keyboard?
Yes. Type numbers, operators and function names directly; Enter calculates, Backspace deletes and Escape clears.
Why do I get “Not a real number”?
The result would be complex, for example the square root of a negative number or asin(2). This calculator works with real numbers only.