Casio fx-991EX Scientific Calculator for advanced engineering, complex statistics and matrix calculations with 552 functions, high-resolution LCD screen, solar power with battery back-up, available in black, blue or pink
Casio fx-991EX Advanced Scientific Calculator for Engineering and Statistical Analysis

The Casio fx-991EX represents a significant step up in computational capability for students tackling A-Level mathematics, university-level STEM subjects including engineering, physics and economics, and professionals requiring reliable technical calculations. With 552 built-in functions, this calculator moves beyond basic arithmetic to handle complex statistical distributions, matrix operations, vector calculations and equation solving that are essential for advanced coursework and technical problem-solving. The high-resolution LCD screen clearly displays spreadsheets, formulae and iterative results, while the solar power system with battery back-up ensures you won't be caught without power during critical calculations. Available in black, blue or pink, this calculator combines serious functionality with personal choice in a durable ABS plastic casing measuring 8.9x18x2.8 cm and weighing 160 grams.
Features and Construction

The fx-991EX is designed specifically for the demanding mathematical environments of advanced education and technical professions, offering functionality that basic calculators cannot provide.
Material and Build
The calculator's housing is constructed from ABS plastic, a material chosen for its balance of durability, light weight and impact resistance. This makes the calculator robust enough for daily use in bags and on desks while keeping the total weight to just 160 grams. The keyboard features clearly labelled buttons for accessing the 552 functions, with colour-coded secondary functions that help users navigate the extensive capabilities without confusion. The solar panel is integrated into the design, providing primary power while maintaining the calculator's streamlined profile.
Size and Practical Fit
With dimensions of 8.9 cm in width, 18 cm in length and 2.8 cm in depth, the fx-991EX offers a substantial display and keyboard area while remaining portable enough for classroom, library or office use. The 160-gram weight makes it easy to carry alongside textbooks and notebooks without adding noticeable bulk. The size accommodates the high-resolution LCD screen needed to properly display complex formulae, statistical tables and spreadsheet matrices that are central to its advanced functionality.
Uses and Placement

This calculator fills a specific niche between basic scientific models and specialised computer software, offering portable, reliable calculation power for specific educational and professional scenarios.
Event or Professional Use
In examination settings where graphing calculators or computers may not be permitted, the fx-991EX provides legitimate advanced functionality for statistics papers, engineering mathematics assessments and economics calculations. Professionals in fieldwork, engineering consultations or quick technical verifications can rely on its matrix calculation capabilities and statistical functions without needing to return to a computer. The solar power with battery back-up ensures functionality in various lighting conditions, from brightly lit offices to less-ideal fieldwork situations.
Everyday Home Use
For university students working on problem sets, the calculator handles the iterative calculations, statistical analysis and equation solving required for physics, engineering and advanced mathematics courses. Economics students can utilise its spreadsheet functionality for data analysis, while the clear display helps prevent errors during lengthy calculation sequences. The choice of black, blue or pink colour options allows users to select a calculator that fits their personal style while providing serious academic functionality.
Benefits and Buying Value

The fx-991EX offers specific advantages over both simpler calculators and more complex computer-based solutions, particularly in educational and portable professional contexts.
Reuse and Low Maintenance
The solar power system reduces dependence on battery replacement, while the battery back-up provides security when lighting conditions are less than ideal. The ABS plastic casing resists the scratches and minor impacts typical of daily academic use, maintaining legibility of labels and display clarity over time. With proper care using a soft, dry cloth for cleaning, the calculator should provide reliable service throughout A-Level studies, undergraduate degrees and into professional use.
Why Choose This Product
This calculator addresses the specific gap between basic scientific models that lack advanced statistical and matrix capabilities and graphing calculators that may not be permitted in certain examination settings. The 552 functions cover the majority of mathematical operations required for STEM subjects without venturing into the territory of programmable devices that might be restricted in formal assessments. The combination of solar power, battery back-up, high-resolution display and durable construction creates a reliable tool for demanding academic and light professional use where computational accuracy and clarity are paramount.






