Node.js console.warn() Function Last Updated : 12 Jul, 2025 Comments Improve Suggest changes Like Article 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 More info T Twinkl Bajaj Follow Improve Article Tags : Web Technologies Node.js NodeJS-function Node.js-console-module Explore Node.js Tutorial 4 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