CASIOfx-991EX
CLASSWIZ
CLASSWIZ
NATURAL TEXTBOOK DISPLAY

About Pocket 991

Scientific and graphing calculators, with an optional teaching layer.

CalculateUse the EX, CW or CG50 controls. Each model keeps its own settings, memories and history.
Get helpTap HELP to ask about the current screen, check whether an operation is supported, or start a highlighted-key walkthrough.
Learn safelyA guide protects your current work. Return restores it; Take over keeps the example and leaves your earlier work recoverable.
Implementation and limitations

Pocket 991 is an independent educational recreation, not Casio firmware or an official Casio app. Numerical precision, some menu paths, input editing, formatting and error behaviour can differ from physical calculators.

QR services, authenticity checks and hardware diagnostics are not reproduced. Numerical integration and symbolic output have documented limits. See the included feature audit for detailed coverage.