JavaScript: Convert a Unix timestamp to time

JavaScript Datetime: Exercise-17 with Solution

Unix to Time

Write a JavaScript function to convert a Unix timestamp to time.

Test Data:
console.log(Unix_timestamp(1412743274));
10:11:14

Sample Solution:

JavaScript Code:

// Define a JavaScript function called Unix_timestamp with parameter t
function Unix_timestamp(t)
{
// Create a new Date object representing the UNIX timestamp multiplied by 1000 (to convert seconds to milliseconds) and store it in the variable dt
var dt = new Date(t*1000);
// Extract the hours component from the Date object and store it in the variable hr
var hr = dt.getHours();
// Extract the minutes component from the Date object and store it in the variable m
var m = "0" + dt.getMinutes();
// Extract the seconds component from the Date object and store it in the variable s
var s = "0" + dt.getSeconds();
// Construct and return a string representation of the time in the format 'hours:minutes:seconds'
return hr+ ':' + m.substr(-2) + ':' + s.substr(-2);  
}

// Output the formatted time for the UNIX timestamp 1412743274
console.log(Unix_timestamp(1412743274));

Output:

10:11:14

Explanation:

In the exercise above,

• The code defines a JavaScript function named "Unix_timestamp()" with one parameter 't', which represents a UNIX timestamp (number of seconds since January 1, 1970).
• Inside the function:
• It creates a new Date object named 'dt' by converting the UNIX timestamp to milliseconds (by multiplying it by 1000).
• It extracts the hours component from the 'dt' Date object and stores it in the variable 'hr'.
• It extracts the minutes component from the 'dt' Date object, pads it with a leading zero if necessary (using the "substr()" method), and stores it in the variable 'm'.
• It extracts the seconds component from the 'dt' Date object, pads it with a leading zero if necessary (using the "substr()" method), and stores it in the variable 's'.
• It constructs a string representation of the time in the format 'hours:minutes:seconds' and returns it.
• The code then demonstrates the usage of the "Unix_timestamp()" function by calling it with the UNIX timestamp 1412743274.

Flowchart:

Live Demo:

See the Pen JavaScript - Convert a Unix timestamp to time-date-ex- 17 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript function that converts a Unix timestamp (in seconds) to a human-readable time string.
• Write a JavaScript function that creates a Date object from a Unix timestamp and outputs the time in HH:MM:SS format.
• Write a JavaScript function that handles both Unix timestamps in seconds and milliseconds for conversion.
• Write a JavaScript function that validates the timestamp input and returns an error if it is not a number.

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