JavaScript Console Log: Best Logging Techniques

2 min readAug 12, 2024

The console is a basic instrument for producing messages, troubleshooting mistakes, and assessing code performance when building JavaScript online apps. Some of the primary JavaScript console techniques will be discussed in this article, arranged based on their unique characteristics and applications.

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Methods of logging levels:

Console.log()

General messages are printed onto the console using the console.log() function. Printing debugging information and tracking program flow is most usually accomplished using this approach.

console.log ( "Common log message" );

2. Console.warn()

The console.warn() function prints warning messages on the console. It aids in directing attention to critical information that requires attention but is not incorrect.

console . warn ( "Warning: Incorrect value" );

3. console.error()

The console.error() method prints error messages to the console. It is used to display critical concerns affecting the application’s proper operation.

console.error("Error: Variable not defined");

Time and Performance Methods:

4. console.time() &console.timeEnd()

These methods are used to determine the execution time of a certain section of code. The code to be measured is preceded by console.time(“name”), followed by console.timeEnd(“name”).

console.time( "Time To Start" ); 

console.timeEnd( "Time To End" );

Data Visualization and Structuring Methods:

5. console.table()

The console.table() method displays data as a table, allowing you to view arrays and objects in a structured, legible fashion.

const data = [
  { id: 1, name: "Eve" },
  { id: 2, name: "Frank" },
  { id: 3, name: "Grace" }
];

console.table(data);

Stack Trace Methods:

6. console.trace()

The console.trace() method displays a complete stack trace, which can help you determine the source of a mistake or a specific execution flow in your code.

function start() {
  process();
}

function process() {
  console.trace('Trace in process function');
}

start(); // Call function start to see the trace

Other Useful Methods:

In addition to the techniques described above for logging levels, time, and performance, JavaScript includes many console methods that can be useful in a variety of situations. Some of these include:

console.clear(): Clears the console.
console.assert(): returns an error message if the supplied statement is false.
console.group()/console.groupEnd(): Groups messages on the console for easier display.

In summary, JavaScript console methods are effective tools for developing, debugging, and evaluating the performance of web applications. Knowing how to utilise each of these techniques can help you better comprehend your code and its console output.

Let me know in the comments if you’re familiar with these JavaScript console methods.