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 Create Quiz 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 Introduction & Installation NodeJS Introduction3 min readNode.js Roadmap: A Complete Guide6 min readHow to Install Node.js on Linux6 min readHow to Install Node.js on Windows5 min readHow to Install NodeJS on MacOS6 min readNode.js vs Browser - Top Differences That Every Developer Should Know6 min readNodeJS REPL (READ, EVAL, PRINT, LOOP)4 min readExplain V8 engine in Node.js7 min readNode.js Web Application Architecture3 min readNodeJS Event Loop5 min readNode.js Modules , Buffer & StreamsNodeJS Modules5 min readWhat are Buffers in Node.js ?4 min readNode.js Streams4 min readNode.js Asynchronous ProgrammingAsync Await in Node.js3 min readPromises in NodeJS7 min readHow to Handle Errors in Node.js ?4 min readException Handling in Node.js3 min readNode.js NPMNodeJS NPM6 min readSteps to Create and Publish NPM packages7 min readIntroduction to NPM scripts2 min readNode.js package.json4 min readWhat is package-lock.json ?3 min readNode.js Deployments & CommunicationNode Debugging2 min readHow to Perform Testing in Node.js ?2 min readUnit Testing of Node.js Application5 min readNODE_ENV Variables and How to Use Them ?2 min readDifference Between Development and Production in Node.js3 min readBest Security Practices in Node.js4 min readDeploying Node.js Applications5 min readHow to Build a Microservices Architecture with NodeJS3 min readNode.js with WebAssembly3 min readResources & ToolsNode.js Web Server6 min readNode Exercises, Practice Questions and Solutions4 min readNode.js Projects9 min readNodeJS Interview Questions and Answers15+ min read Like