Calculator Usage Tutorial

Welcome to the Accessible Calculator tutorial! This guide will walk you through using our calculator, which is designed for everyone, including those who rely on keyboards or screen readers. Whether you're doing simple math or advanced calculations, you'll find step-by-step instructions here.

Calculator usage guide and tutorial illustration

Getting Started

The calculator has two modes: Basic and Scientific. Start with Basic for everyday math like addition, subtraction, multiplication, and division. Switch to Scientific for functions like sine, cosine, square root, and logarithms.

To access the calculator, visit the Calculator / BMI page. The interface is clean and straightforward, with large buttons for easy clicking or tapping.

Basic Calculator Usage

Basic mode handles standard arithmetic. Here's how to perform a simple calculation:

  1. Click the "Calculator" tab if it's not already selected.
  2. Ensure "Basic" is chosen under Calculator type.
  3. Enter the first number using the number buttons (0-9) or your keyboard.
  4. Select an operator: + for addition, - for subtraction, × for multiplication, ÷ for division.
  5. Enter the second number.
  6. Press the = button to see the result in the display.

Example: To calculate 15 + 27, enter 1, 5, +, 2, 7, =, and the display shows 42.

Use the Clear button to reset, or Backspace to remove the last digit. The display shows your input and results clearly.

Scientific Functions with Examples

Scientific mode unlocks advanced math. Switch by selecting "Scientific" under Calculator type. Additional buttons appear for functions.

Trigonometric Functions

Use sin, cos, and tan for angles. Input is in radians by default.

Example: To find the sine of 1 radian, enter 1, press sin, then =, resulting in approximately 0.8415.

Square Root and Powers

√ calculates square roots, x² squares a number.

Example: Square root of 16: Enter 16, press √, =, displays 4.

Example: 5 squared: Enter 5, press x², =, displays 25.

Logarithms and Exponentials

log is the base-10 logarithm, exp is e raised to a power.

Example: Log of 100: Enter 100, press log, =, displays 2.

Example: e^2: Enter 2, press exp, =, displays approximately 7.389.

Combine functions with operators for complex calculations, like sin(0.5) + 3.

How to Use the BMI Calculator

The BMI Calculator helps you determine your Body Mass Index using your weight and height. It's a useful tool for understanding your general health category.

Switching to BMI Mode

On the calculator page, locate and select the "BMI" tab. This switches the interface to BMI calculation mode, showing fields for weight, height, and a calculate button.

Entering Your Measurements

  1. Select the "BMI" tab to activate BMI mode.
  2. Locate the weight input field, labeled "Weight (kg)".
  3. Enter your weight in kilograms using the number keys or your keyboard.
  4. Locate the height input field, labeled "Height (meters)".
  5. Enter your height in meters (e.g., 1.75 for 175 cm).

Calculating Your BMI

  1. After entering both weight and height, locate the "Calculate BMI" button.
  2. Press the button or press Enter/Space while focused on it.
  3. Your BMI result will appear in the result field labeled "BMI result".

Understanding Your Results

BMI values fall into categories:

  • Under 18.5: Underweight
  • 18.5–24.9: Normal weight
  • 25–29.9: Overweight
  • 30 and above: Obese

Accessibility Features

The BMI Calculator is fully accessible:

  • All input fields have proper labels for screen readers.
  • Use Tab to move between weight and height fields.
  • Results are announced via live regions after calculation.
  • Inputs accept only valid numbers (decimal values allowed).

For more detailed information about BMI, its interpretation, and limitations, visit our Calculator page.

Keyboard-Only Navigation

The calculator works fully with keyboards—no mouse needed. This is great for users with motor disabilities or those preferring keyboard input.

  • Use Tab to move between buttons and the display.
  • Press Enter or Space to activate buttons.
  • Type numbers directly into the display when focused.
  • Use arrow keys to navigate if supported by your browser.

The hamburger menu in the header also supports keyboard: Tab to it, press Enter or Space to open, then Tab through links.

Focus indicators highlight the active element, making navigation clear.

Screen Reader Usage Tips

Screen readers announce buttons, results, and changes dynamically. The calculator uses ARIA labels and live regions for accessibility.

  • Buttons are labeled clearly, e.g., "button, 5" or "button, add".
  • The display announces results via a live region.
  • Tabs are role-based, so screen readers know they're switchable.
  • Forms have proper labels for inputs.

When you press a button or get a result, the screen reader will announce it. For example, after calculating, it might say "Result: 42".

This design empowers visually impaired users to do math confidently, reducing reliance on others and promoting self-sufficiency.

This tutorial covers the essentials to get you started. Experiment with the calculator and refer back as needed. For more on accessibility, check the main site. Happy calculating!