Node.js console.warn() Function Last Updated : 12 Jul, 2025 Comments Improve Suggest changes 1 Likes Like Report The console.warn() function from console class of Node.js is used to display the warning messages on the console. It prints to stderr with newline. Note: This function is an alias of console.error() function. Syntax: console.warn( [data][, ...args] ) Parameter: This function can contains multiple parameters. The first parameter is used for the primary message and other parameters are used for substitution values. Return Value: The function returns the warning message. Below programs demonstrate the working of the console.warn() function: Program 1: javascript function displayWarning(x) { console.warn(`GeeksforGeeks is a ${x} portal`); } const x = 'Computer Science'; displayWarning(x); Output: GeeksforGeeks is a Computer Science portal Program 2: javascript function compareNumber(x, y) { // Check condition if (x > y) { console.warn(`${x} is greater then ${y}`); } else { console.warn(`${x} is less then or equal to ${y}`); } } // Store number to variable x = 100; y = 50; compareNumber(x, y); Output: 100 is greater then 50 Comment T Twinkl Bajaj Follow 1 Improve T Twinkl Bajaj Follow 1 Improve Article Tags : Web Technologies Node.js NodeJS-function Node.js-console-module Explore Node.js Tutorial 3 min read Introduction & Installation NodeJS Introduction 3 min read Node.js Roadmap: A Complete Guide 6 min read How to Install Node.js on Linux 6 min read How to Install Node.js on Windows 5 min read How to Install NodeJS on MacOS 6 min read Node.js vs Browser - Top Differences That Every Developer Should Know 6 min read NodeJS REPL (READ, EVAL, PRINT, LOOP) 4 min read Explain V8 engine in Node.js 7 min read Node.js Web Application Architecture 3 min read NodeJS Event Loop 5 min read Node.js Modules , Buffer & StreamsNodeJS Modules 5 min read What are Buffers in Node.js ? 4 min read Node.js Streams 4 min read Node.js Asynchronous ProgrammingAsync Await in Node.js 3 min read Promises in NodeJS 7 min read How to Handle Errors in Node.js ? 4 min read Exception Handling in Node.js 3 min read Node.js NPMNodeJS NPM 6 min read Steps to Create and Publish NPM packages 7 min read Introduction to NPM scripts 2 min read Node.js package.json 4 min read What is package-lock.json ? 3 min read Node.js Deployments & CommunicationNode Debugging 2 min read How to Perform Testing in Node.js ? 2 min read Unit Testing of Node.js Application 5 min read NODE_ENV Variables and How to Use Them ? 2 min read Difference Between Development and Production in Node.js 3 min read Best Security Practices in Node.js 4 min read Deploying Node.js Applications 5 min read How to Build a Microservices Architecture with NodeJS 3 min read Node.js with WebAssembly 3 min read Resources & ToolsNode.js Web Server 6 min read Node Exercises, Practice Questions and Solutions 4 min read Node.js Projects 9 min read NodeJS Interview Questions and Answers 15+ min read Like