Introduction
The Casio FX-9860GIII is an advanced graphing calculator designed for a wide range of mathematical, scientific, and financial applications. Featuring a 128 x 64 dot wide LCD display with backlight, it offers enhanced readability and simplified use with natural format expression input and output. This model supports Python programming and includes over 2,900 functions, making it suitable for students and professionals in various fields.

Figure 1: Front view of the Casio FX-9860GIII Graphing Calculator, showing the display and key layout.
Video 1: Official product video showcasing the Casio calculator's features and design.
Setup
Battery Installation
The Casio FX-9860GIII requires 4 AAA batteries (not supplied with the product). To install or replace batteries:
- Ensure the calculator is turned off.
- Slide off the back cover of the calculator.
- Carefully remove any old batteries.
- Insert four new AAA batteries, ensuring correct polarity (+/-).
- Replace the back cover, ensuring it clicks securely into place.
Initial Power On
Press the [AC/ON] button to turn on the calculator. The initial screen may display a setup menu or a blank calculation screen.
PC Interface via USB
The calculator features a USB interface for direct data communication with a PC or projector. Use the provided USB cable to connect the calculator to your computer. Refer to the Casio website for driver installation and software utilities required for data transfer and advanced functionalities.
Operating Instructions
The FX-9860GIII offers a comprehensive suite of functions accessible through its intuitive menu system and dedicated keys.
Basic Calculations
- Arithmetic Operations: Use the standard [+], [-], [x], [/] keys.
- Fractions: Input fractions using the [a b/c] key.
- Percentages: Use the [%] key for percentage calculations.
- Reciprocal: The [x^-1] key calculates the reciprocal of a value.
Mathematical Functions
- Trigonometry: Access sine ([sin]), cosine ([cos]), tangent ([tan]), and their inverse functions.
- Exponentials & Logarithms: Use [e^x], [10^x], [ln], and [log] keys.
- Absolute Value: Use the [Abs] function.
- Combinations/Permutations: Available through the [OPTN] menu.
- GCD/LCM: Greatest Common Divisor and Least Common Multiple functions are included.
- Random Number: Generate random numbers using the appropriate function.
Graphing Functions
The calculator supports various graphing modes:
- Parametric Graphics: Plot equations defined by a parameter.
- Inequality Graph: Visualize inequalities.
- Polar Functions: Graph functions in polar coordinates.
- Zoom & Trace: Use [Zoom] and [Trace] functions to analyze graphs.
Statistical Functions
- List-Based Data Editor: Input and manage statistical data.
- Regression Analysis: Perform linear, med-med, square, cubic, quartic, logarithm, exponential, power, sinusoidal, and logistics regression.
- Advanced Statistics: Includes testing, ranges, and distributions.
- Plotting: Create dispersion, XY, normal probability, histogram, box, pizza, and bar charts.
Financial Functions
Access a dedicated menu for financial calculations:
- Simple and Compound Interest
- Effective Interest
- Installments and Amortization
- Rate Conversion
- Cash Flow Analysis
- Cost, Price, and Margin Calculations
- Date/Day Calculations
- Depreciation
- YLD (Annual Income) and Investment Appraisal
eActivity
The eActivity feature allows you to create and store interactive notebooks. You can insert text, mathematical expressions, and other data, building data file applications directly on the calculator.
Python Programming
The FX-9860GIII supports Python programming, enabling users to write and execute custom scripts for advanced computations and problem-solving. Access the Python environment through the main menu.
Exam Mode
Activate Exam Mode to restrict certain functions during tests, ensuring compliance with examination regulations. Consult your exam board's guidelines for approved calculator models and modes.
Maintenance
Cleaning
Wipe the calculator's exterior with a soft, dry cloth. Avoid using abrasive cleaners or solvents, as these can damage the casing and screen.
Battery Care
If the calculator will not be used for an extended period, remove the AAA batteries to prevent leakage and potential damage. When using the USB interface for power, ensure the connection is secure.
Storage
Store the calculator in a cool, dry place, away from direct sunlight and extreme temperatures. Use the hard case provided to protect it from physical damage.
Troubleshooting
Calculator Does Not Turn On
- Check if the AAA batteries are correctly installed and have sufficient charge. Replace if necessary.
- Ensure the [AC/ON] button is pressed firmly.
Display Issues
- If the display is dim, adjust the contrast settings via the [SET UP] menu.
- If the display is blank or shows unusual characters, try resetting the calculator (refer to the full manual for reset procedures).
Incorrect Calculation Results
- Verify the input values and the calculation mode (e.g., radian/degree mode for trigonometry).
- Ensure all previous calculations are cleared before starting a new one.
Specifications
| Feature | Detail |
|---|---|
| Brand | Casio |
| Model Name | FX-9860GIII |
| Calculator Type | Graphing |
| Display Type | LCD (128 x 64 dot wide) with backlight |
| Power Source | Battery Powered (4 AAA batteries required) |
| Screen Size | 6.4 Centimeters |
| Item Dimensions (L x W) | 6.91"L x 3.29"W (approx. 17.6 cm x 8.4 cm) |
| Item Weight | 190 Grams |
| Enclosure Material | Plastic |
| Functions | Over 2,900 (Math, Statistics, Physics, Chemistry, Finance, Python) |
| Memory | User Memory: 62 Kbytes, User Storage Memory: 3M Bytes |
| Connectivity | USB interface |

Figure 2: The Casio FX-9860GIII calculator shown alongside a ruler, illustrating its approximate dimensions of 176mm in length and 84mm in width.
Warranty and Support
For warranty information, please refer to the documentation included with your product packaging or visit the official Casio website. Technical support and additional resources can also be found on the Casio support pages.





