Scientific Calculator
Free online scientific calculator with trigonometry, logarithms, and advanced functions. Works on mobile and desktop.
How this calculator works
Expressions are evaluated with math.js, which applies correct order of operations (PEMDAS/BODMAS), supports parentheses, powers (^), and standard functions. Choose Deg or Rad for sine, cosine, tangent, and their inverses.
log is base 10; ln is the natural logarithm. n! inserts a factorial (e.g. 5!). Use MC / MR / M+ / M− for memory after you have a valid result (evaluate with = or use memory keys which evaluate the current line when needed).
Frequently asked questions
What library evaluates expressions?
We load math.js from a CDN and use it to parse and evaluate your expression string with standard operator precedence.
What is the difference between Deg and Rad?
Trigonometric functions use degrees in Deg mode and radians in Rad mode. Toggle with the mode button before evaluating sin, cos, or tan.
Why does my expression show an error?
Unbalanced parentheses, invalid function names, division by zero, or domain errors (like log of a negative number) all surface as errors instead of silent wrong answers.
How do memory keys work?
MC clears stored memory, MR recalls it, and M+ / M− add or subtract the current evaluated value. Some actions evaluate the visible line first.
Does the calculator work fully offline?
After the math.js script has been cached by your browser it may work offline, but the first visit needs network access to load the library.
Are calculations sent to DoItSwift servers?
No. Evaluation happens locally in your browser once math.js is available.