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Free Casio-style scientific calculator
Casio Scientific
Calculator Online
A free online scientific calculator with a Casio-style layout — trigonometry, logarithms, powers, roots, fractions and scientific notation, ready in your browser with no download.
8Languages
6Color themes
100%Free forever
Casio FX-991ES Scientific Calculator View
CASIO STYLEfx-991ES PLUS inspired
DEGREADY
0
REPLAY
Calculation History
No history yet...
Features
Core scientific calculator functions
Trig modes
Switch between DEG and RAD for sine, cosine, tangent and inverse trig functions.
History & keyboard
Reuse your last answer and type expressions straight from a desktop keyboard.
How to use
Enter, calculate, reuse results
1
Enter an expression
Tap the keys or use your keyboard to type numbers, operators and functions.
2
Choose DEG or RAD
Set the angle mode before calculating any trigonometric expression.
3
Press equals
See the result instantly, then reuse it with Ans in your next calculation.
Online scientific calculator
A fast Casio-style scientific calculator for everyday math
Built for practical calculations
This free scientific calculator online gives students, teachers and engineers a familiar Casio calculator online layout — no account or install needed.
Useful for school and engineering work
Use this casio scientific calculator online for trigonometry, logarithms, physics formulas and everyday arithmetic, with DEG/RAD to match your textbook.
Mobile-friendly scientific calculator
Large touch keys work well on phones and tablets, while full keyboard support keeps desktop use fast.
Model & function guide
Popular scientific calculator casio searches
Casio fx-991EX scientific calculator online
A popular model among students — practice the same functions here in a browser-based scientific calculator.
Casio fx-991ES Plus online
Use an online scientific calculator for fractions, trigonometry, powers, roots and logarithms.
Casio fx-570MS and fx-570ES
Looking for an fx-570MS or fx-570ES online? Use this browser calculator for the same core operations.
Scientific calculator with fractions
Work with fractional values for algebra, geometry and physics, and check them against decimal results.
SHIFT and advanced functions
A familiar SHIFT control reaches extra operations alongside trig, log and root functions.
Scientific calculator emulator & app alternative
A calculator casio online free alternative to installing an app — works on desktop and mobile browsers.
FAQ
Common questions
Is this an official Casio calculator?
No. This is an independent casio calculator online free tool with a Casio-style layout. Casio and its model names belong to their owner.
Is this calculator free?
Yes — this casio online calculator free tool works directly in your browser at no cost.
Does it work on mobile?
Yes. The layout is responsive across phones, tablets and desktop browsers.
Does it support fractions?
It's built around scientific calculation workflows, including fraction-related work.
What is DEG/RAD mode?
DEG reads angles in degrees; RAD reads them in radians — match the mode to your formula.
Can I use it for school or exams?
Use it for practice and everyday calculation, but always follow your school's or exam board's calculator rules.