The TI-84 Plus is the gold standard for high school and college mathematics. Our online graphing calculator emulator allows you to visualize functions, explore mathematical relationships, and prepare for exams like the SAT, ACT, and AP Calculus without needing the physical handheld device.
How to Use the Online Grapher
To begin graphing, enter your algebraic expression in the f(x) input field. Unlike a physical TI-84 where you might press "x,t,θ,n", here you simply type 'x'. For exponents, use standard programming syntax like x * x or Math.pow(x, 2).
X-Range: Determines the horizontal width of the viewing window.
Y-Range: Determines the vertical height of the viewing window.
Syntax: Ensure you use * for multiplication (e.g., 2*x instead of 2x).
Common TI-84 Function Examples
Math Type
Expression Input
Linear
2*x + 3
Quadratic
x*x – 4
Sine Wave
Math.sin(x)
Absolute Value
Math.abs(x)
Why Use an Online TI-84 Simulator?
A physical TI-84 Plus CE can cost over $100. Online alternatives provide students with a free way to practice graphing parabolas, finding intercepts, and understanding function transformations. This tool mimics the logic of the Texas Instruments OS, helping you build the muscle memory required for classroom success.
function drawGraph() {
var canvas = document.getElementById('graphCanvas');
var ctx = canvas.getContext('2d');
var funcStr = document.getElementById('functionInput').value;
var xMin = parseFloat(document.getElementById('xMin').value);
var xMax = parseFloat(document.getElementById('xMax').value);
var yMin = parseFloat(document.getElementById('yMin').value);
var yMax = parseFloat(document.getElementById('yMax').value);
if (isNaN(xMin) || isNaN(xMax) || isNaN(yMin) || isNaN(yMax)) {
alert("Please enter valid window numbers.");
return;
}
// Clear and draw background
ctx.clearRect(0, 0, canvas.width, canvas.height);
ctx.fillStyle = "#9eb19e";
ctx.fillRect(0, 0, canvas.width, canvas.height);
// Draw Axes
ctx.strokeStyle = "#555";
ctx.lineWidth = 1;
// X-axis
var xAxisY = canvas.height – ((0 – yMin) / (yMax – yMin) * canvas.height);
ctx.beginPath();
ctx.moveTo(0, xAxisY);
ctx.lineTo(canvas.width, xAxisY);
ctx.stroke();
// Y-axis
var yAxisX = (0 – xMin) / (xMax – xMin) * canvas.width;
ctx.beginPath();
ctx.moveTo(yAxisX, 0);
ctx.lineTo(yAxisX, canvas.height);
ctx.stroke();
// Draw Function
ctx.strokeStyle = "#000";
ctx.lineWidth = 2;
ctx.beginPath();
var firstPoint = true;
for (var i = 0; i <= canvas.width; i++) {
var xVal = xMin + (i / canvas.width) * (xMax – xMin);
var yVal;
try {
// Basic sanitization and evaluation
// Replacing 'x' with the value and making math functions accessible
var evalStr = funcStr.toLowerCase().replace(/x/g, "(" + xVal + ")");
// We use Function constructor for a bit better safety than eval but still dynamic
yVal = new Function('return ' + evalStr)();
} catch (e) {
console.log("Error in function");
break;
}
var canvasY = canvas.height – ((yVal – yMin) / (yMax – yMin) * canvas.height);
if (firstPoint) {
ctx.moveTo(i, canvasY);
firstPoint = false;
} else {
ctx.lineTo(i, canvasY);
}
}
ctx.stroke();
}
function clearCanvas() {
var canvas = document.getElementById('graphCanvas');
var ctx = canvas.getContext('2d');
ctx.clearRect(0, 0, canvas.width, canvas.height);
ctx.fillStyle = "#9eb19e";
ctx.fillRect(0, 0, canvas.width, canvas.height);
document.getElementById('functionInput').value = "";
}
// Initial grid state
window.onload = function() {
var canvas = document.getElementById('graphCanvas');
var ctx = canvas.getContext('2d');
ctx.fillStyle = "#9eb19e";
ctx.fillRect(0, 0, canvas.width, canvas.height);
};