diff --git a/Data-Structures/Stack/EvaluateExpression.js b/Data-Structures/Stack/EvaluateExpression.js
new file mode 100644
index 0000000000..e59a4a37c0
--- /dev/null
+++ b/Data-Structures/Stack/EvaluateExpression.js
@@ -0,0 +1,58 @@
+/**
+ * Evaluate a numeric operations string in postfix notation using a stack.
+ * Supports basic arithmetic operations: +, -, *, /
+ * @see https://www.geeksforgeeks.org/evaluation-of-postfix-expression/
+ * @param {string} expression - Numeric operations expression to evaluate. Must be a valid postfix expression.
+ * @returns {number|null} - Result of the expression evaluation, or null if the expression is invalid.
+ */
+function evaluatePostfixExpression(expression) {
+ const stack = [];
+
+ // Helper function to perform an operation and push the result to the stack. Returns success.
+ function performOperation(operator) {
+ const rightOp = stack.pop(); // Right operand is the top of the stack
+ const leftOp = stack.pop(); // Left operand is the next item on the stack
+
+ if (leftOp === undefined || rightOp === undefined) {
+ return false; // Invalid expression
+ }
+ switch (operator) {
+ case '+':
+ stack.push(leftOp + rightOp);
+ break;
+ case '-':
+ stack.push(leftOp - rightOp);
+ break;
+ case '*':
+ stack.push(leftOp * rightOp);
+ break;
+ case '/':
+ if (rightOp === 0) {
+ return false;
+ }
+ stack.push(leftOp / rightOp);
+ break;
+ default:
+ return false; // Unknown operator
+ }
+ return true;
+ }
+
+ const tokens = expression.split(/\s+/);
+
+ for (const token of tokens) {
+ if (!isNaN(parseFloat(token))) {
+ // If the token is a number, push it to the stack
+ stack.push(parseFloat(token));
+ } else {
+ // If the token is an operator, perform the operation
+ if (!performOperation(token)) {
+ return null; // Invalid expression
+ }
+ }
+ }
+
+ return (stack.length === 1) ? stack[0] : null;
+}
+
+export { evaluatePostfixExpression };
diff --git a/Data-Structures/Stack/test/EvaluateExpression.test.js b/Data-Structures/Stack/test/EvaluateExpression.test.js
new file mode 100644
index 0000000000..eea764cac2
--- /dev/null
+++ b/Data-Structures/Stack/test/EvaluateExpression.test.js
@@ -0,0 +1,22 @@
+import { evaluatePostfixExpression } from '../EvaluateExpression.js';
+
+describe('evaluatePostfixExpression', () => {
+ it('should evaluate a valid expression', () => {
+ const expression = '3 4 * 2 / 5 +'; // (3 * 4) / 2 + 5 = 11
+ const result = evaluatePostfixExpression(expression);
+ expect(result).toBe(11);
+ });
+
+ it('should handle division by zero', () => {
+ const expression = '3 0 /'; // Division by zero
+ const result = evaluatePostfixExpression(expression);
+ expect(result).toBe(null);
+ });
+
+ it('should handle an invalid expression', () => {
+ const expression = '3 * 4 2 / +'; // Invalid expression
+ const result = evaluatePostfixExpression(expression);
+ expect(result).toBe(null);
+ });
+
+});
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