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I have this object:

const myObject = {
   "a":"a",
   "b":{
      "c":"c",
      "d":{
         "e":"e",
         "f":{
            "g":"g",
            "h":{
               "i":"i"
            }
         }
      }
   }
};

But when I try to show it using console.log(myObject), I receive this output:

{ a: 'a', b: { c: 'c', d: { e: 'e', f: [Object] } } }

How can I get the full object, including the content of property f?

I have this object:

const myObject = {
   "a":"a",
   "b":{
      "c":"c",
      "d":{
         "e":"e",
         "f":{
            "g":"g",
            "h":{
               "i":"i"
            }
         }
      }
   }
};

But when I try to show it using console.log(myObject), I receive this output:

{ a: 'a', b: { c: 'c', d: { e: 'e', f: [Object] } } }

How can I get the full object, including the content of property f?

• javascript
• node.js
• debugging
• console.log

Share Improve this question Follow edited Apr 9, 2022 at 22:45 lifeisfoo 16.3k66 gold badges7878 silver badges127127 bronze badges asked May 23, 2012 at 23:29 user1372449user1372449 4

• 145 Note that back in 2012 this was a problem in need of a solution, but this has (long) since been solved with the introduction of console.dir, which takes an options object that lets you specify the printing depth, with null for unlimited depth: console.dir(yourObject, { depth: null });. The highest voted answers for this question were all great answers back when they were written, but have since become obsolete over the course of a decade of improvements. The modern answer is simply "use console.dir". – Mike 'Pomax' Kamermans Commented Sep 11, 2021 at 17:44
• 1 I guess a best practice for StackOverflow users would be to use "Sorted by: Date modified (newest first)" if a question is old enough. Answer from mklement0 also suggests to use console.dir – Devin Rhode Commented Aug 21, 2023 at 20:14
• console.dir is helpful but not as robust as console.log. The latter lets you log things like console.log("a", b, "c"). To get similar output with console.dir you'd need to do something like console.log("a"); console.dir(b); console.log("c"). Better yet (?), you could do this: console.log("a", util.inspect(b), "c") – Daniel Kaplan Commented May 18, 2024 at 20:36
• Do this*: require('util').inspect.defaultOptions.depth = 10 In my case I have a pretty big project with all sorts of logging variability, like single and multiple parameter logging, strings, objects and all combinations of both. So console.dir wasn't an easy switch. That one-liner solved it. *That code smell a bit as changing inbuilt variables doesn't look right. Nonetheless, it solves the issue without the need to change and maintain the entire project's logging approach. No drawbacks so far. Use at your own risk though. Works in node 20, may break if they change it in future. – vir us Commented Jul 29, 2024 at 9:50

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22 Answers 22

Sorted by: Reset to default 2248

You need to use util.inspect():

const util = require('util')

console.log(util.inspect(myObject, {showHidden: false, depth: null, colors: true}))

// alternative shortcut
console.log(util.inspect(myObject, false, null, true /* enable colors */))

Outputs

{ a: 'a',  b: { c: 'c', d: { e: 'e', f: { g: 'g', h: { i: 'i' } } } } }

You can use JSON.stringify, and get some nice indentation as well as perhaps easier to remember syntax.

console.log(JSON.stringify(myObject, null, 4));

---

{
    "a": "a",
    "b": {
        "c": "c",
        "d": {
            "e": "e",
            "f": {
                "g": "g",
                "h": {
                    "i": "i"
                }
            }
        }
    }
}

The third argument sets the indentation level, so you can adjust that as desired.

More detail here in JSON stringify MDN docs if needed.

^{A compilation of the many useful answers from (at least) Node.js `v0.10.33` (stable) / `v0.11.14` (unstable) presumably through (at least) `v7.7.4` (the version current as of the latest update to this answer). Tip of the hat to [Rory O'Kane](https://stackoverflow.com/users/578288/rory-okane) for his help.}

tl;dr

To get the desired output for the example in the question, use console.dir():

console.dir(myObject, { depth: null }); // `depth: null` ensures unlimited recursion

Why not util.inspect()? Because it’s already at the heart of diagnostic output: console.log() and console.dir() as well as the Node.js REPL use util.inspect() implicitly. It’s generally not necessary to require('util') and call util.inspect() directly - unless you want to capture the object visualization in a variable rather than printing to the console (e.g., let s = util.inspect(myObject, { depth: null }))

Details below.

---

• console.log() (and its alias, console.info()):

  • If the 1st argument is NOT a format string: util.inspect() is automatically applied to every argument:
    • o = { one: 1, two: 'deux', foo: function(){} }; console.log(o, [1,2,3]) // -> '{ one: 1, two: 'deux', foo: [Function] } [ 1, 2, 3 ]'
    • Note that you cannot pass options through util.inspect() in this case, which implies 2 notable limitations:
      • Structural depth of the output is limited to 2 levels (the default).
        • Since you cannot change this with console.log(), you must instead use console.dir(): console.dir(myObject, { depth: null } prints with unlimited depth; see below.
      • You can’t turn syntax coloring on.
  • If the 1st argument IS a format string (see below): uses util.format() to print the remaining arguments based on the format string (see below); e.g.:
    • o = { one: 1, two: 'deux', foo: function(){} }; console.log('o as JSON: %j', o) // -> 'o as JSON: {"one":1,"two":"deux"}'
    • Note:
      • There is NO placeholder for representing objects util.inspect()-style.
      • JSON generated with %j is NOT pretty-printed.

• console.dir():

  • Accepts only 1 argument to inspect, and always applies util.inspect() – essentially, a wrapper for util.inspect() without options by default; e.g.:
    • o = { one: 1, two: 'deux', foo: function(){} }; console.dir(o); // Effectively the same as console.log(o) in this case.
  • Node.js v0.11.14+: The optional 2nd argument specifies options for util.inspect() – see below; e.g.:
    • console.dir({ one: 1, two: 'deux'}, { colors: true }); // Node 0.11+: Prints object representation with syntax coloring.

• The REPL: implicitly prints any expression's return value with util.inspect() with syntax coloring;
  i.e., just typing a variable's name and hitting Enter will print an inspected version of its value; e.g.:
  • o = { one: 1, two: 'deux', foo: function(){} } // The REPL echoes the object definition with syntax coloring.

util.inspect() automatically pretty-prints object and array representations, but produces multiline output only when needed.

• The pretty-printing behavior can be controlled by the compact property in the optional options argument; false uses multi-line output unconditionally, whereas true disables pretty-printing altogether; it can also be set to a number (the default is 3) to control the conditional multi-line behavior – see the docs.

• By default, output is wrapped at around 60 characters ^{thanks, Shrey} , regardless of whether the output is sent to a file or a terminal. In practice, since line breaks only happen at property boundaries, you will often end up with shorter lines, but they can also be longer (e.g., with long property values).

• In v6.3.0+ you can use the breakLength option to override the 60-character limit; if you set it to Infinity, everything is output on a single line.

If you want more control over pretty-printing, consider using JSON.stringify() with a 3rd argument, but note the following:

• Fails with objects that have circular references, such as module in the global context.
• Methods (functions) will by design NOT be included.
• You can't opt into showing hidden (non-enumerable) properties.
• Example call:
  • JSON.stringify({ one: 1, two: 'deux', three: true}, undefined, 2); // creates a pretty-printed multiline JSON representation indented with 2 spaces

---

util.inspect() options object (2nd argument):

An optional options object may be passed that alters certain aspects of the formatted string; some of the properties supported are:

^{See the latest Node.js docs for the current, full list.}

• showHidden

  • if true, then the object's non-enumerable properties [those designated not to show up when you use for keys in obj or Object.keys(obj)] will be shown too. Defaults to false.

• depth

  • tells inspect how many times to recurse while formatting the object. This is useful for inspecting large complicated objects. Defaults to 2. To make it recurse indefinitely, pass null.

• colors

  • if true, then the output will be styled with ANSI color codes. Defaults to false. Colors are customizable [… – see link].

• customInspect

  • if false, then custom inspect() functions defined on the objects being inspected won't be called. Defaults to true.

---

util.format() format-string placeholders (1st argument)

Some of the supported placeholders are:

^{See the latest Node.js docs for the current, full list.}

• %s – String.
• %d – Number (both integer and float).
• %j – JSON.
• %% – single percent sign (‘%’). This does not consume an argument.

Since Node.js 6.4.0, this can be elegantly solved with util.inspect.defaultOptions:

require("util").inspect.defaultOptions.depth = null;
console.log(myObject);

Another simple method is to convert it to json

console.log('connection : %j', myObject);

Try this:

console.dir(myObject,{depth:null})

Both of these usages can be applied:

// more compact, and colour can be applied (better for process managers logging)
console.dir(queryArgs, { depth: null, colors: true });

// get a clear list of actual values
console.log(JSON.stringify(queryArgs, undefined, 2));

perhaps console.dir is all you need.

http://nodejs.org/api/console.html#console_console_dir_obj

Uses util.inspect on obj and prints resulting string to stdout.

use util option if you need more control.

A good way to inspect objects is to use node --inspect option with Chrome DevTools for Node.

node.exe --inspect www.js

Open chrome://inspect/#devices in chrome and click Open dedicated DevTools for Node

Now every logged object is available in inspector like regular JS running in chrome.

There is no need to reopen inspector, it connects to node automatically as soon as node starts or restarts. Both --inspect and Chrome DevTools for Node may not be available in older versions of Node and Chrome.

You can also do

console.log(JSON.stringify(myObject, null, 3));

I think this could be useful for you.

const myObject = {
   "a":"a",
   "b":{
      "c":"c",
      "d":{
         "e":"e",
         "f":{
            "g":"g",
            "h":{
               "i":"i"
            }
         }
      }
   }
};

console.log(JSON.stringify(myObject, null, '\t'));

As mentioned in this answer:

JSON.stringify's third parameter defines white-space insertion for pretty-printing. It can be a string or a number (number of spaces).

Use a logger

Don't try to reinvent the wheel

util.inspect(), JSON.stringify() and console.dir() are useful tools for logging an object while playing in the browser console.

If you are serious about Node.js development, you should definitely use a logger. Using it you can add all the logs you want for debugging and monitoring your application. Then just change the logging level of your logger to keep only the production logs visible.

Additionaly they have already solved all the annoying issues related to logging, like: circular objects, formatting, log levels, multiple outputs and performance.

Use a modern logger

pino is a fast and modern logger for Node.js that has sane defaults to handle circular object/references like depthLimit and edgeLimit. It supports child loggers, transports and a pretty printed output.

Moreover, it has 8 default logging levels that you can customize using the customLevels option:

• fatal
• error
• warn
• info
• debug
• trace
• silent

Install it

npm install pino

Use it

const logger = require('pino')()

logger.info('hello world')

Configure it

const logger = pino({
  depthLimit: 10,
  edgeLimit: 200,
  customLevels: {
    foo: 35
  }
});

logger.foo('hi')

JSON.stringify()

let myVar = {a: {b: {c: 1}}};
console.log(JSON.stringify( myVar, null, 4 ))

Great for deep inspection of data objects. This approach works on nested arrays and nested objects with arrays.

You can simply add an inspect() method to your object which will override the representation of object in console.log messages

eg:

var myObject = {
   "a":"a",
   "b":{
      "c":"c",
      "d":{
         "e":"e",
         "f":{
            "g":"g",
            "h":{
               "i":"i"
            }
         }
      }
   }
};
myObject.inspect = function(){ return JSON.stringify( this, null, ' ' ); }

then, your object will be represented as required in both console.log and node shell

---

Update:

object.inspect has been deprecated ( https://github.com/nodejs/node/issues/15549). Use myObject[util.inspect.custom] instead:

const util = require('util')

var myObject = {
  /* nested properties not shown */
}

myObject[util.inspect.custom] = function(){ return JSON.stringify( this, null, 4 ); }


console.log(util.inspect(myObject))

If you're looking for a way to show the hidden items in you array, you got to pass maxArrayLength: Infinity

console.log(util.inspect(value, { maxArrayLength: Infinity }));

A simple trick would be use debug module to add DEBUG_DEPTH=null as environment variable when running the script

Ex.

DEBUG=* DEBUG_DEPTH=null node index.js

In you code

const debug = require('debug');
debug("%O", myObject);

const myObject = {
   "a":"a",
   "b":{
      "c":"c",
      "d":{
         "e":"e",
         "f":{
            "g":"g",
            "h":{
               "i":"i"
            }
         }
      }
   }
};
console.log(JSON.stringify(myObject));

Output:

{"a":"a","b":{"c":"c","d":{"e":"e","f":{"g":"g","h":{"i":"i"}}}}}

Easiest option:

    console.log('%O', myObject);

The node REPL has a built-in solution for overriding how objects are displayed, see here.

The REPL module internally uses util.inspect(), when printing values. However, util.inspect delegates the call to the object's inspect() function, if it has one.

Replace the default console by a customized console as following:

globalThis.console = new console.Console({
  inspectOptions: {
    depth:null,
  },
  stdout:process.stdout,
  stderr:process.stderr,
});

Once the code block is executed, all output of the console.log is formatted as you specified in the inspectOptions.

If you already have a large amount of code which uses console.log, replacing console might be the easiest way to solve the problem.

Accoding to the official reference of Node.js, creating customized consoles as new Console(options) have been available since Node.js version 8.

My way :)

Define function

console.obj = (...args) => args.forEach(obj => console.log(require('util').inspect(obj, false, null, true)));

Usage

const test = {
   "a":"a",
   "b":{
      "c":"c",
      "d":{
         "e":"e",
         "f":{
            "g":"g",
            "h":{
               "i":"i"
            }
         }
      }
   }
};

const test2 = {
   second: 'object'
};

console.obj(test, test2);

For NodeJs 16 and beyond, you can use the below snippet.

require(util).inspect(<your-object-here>, { showHidden: false, depth: null, maxArrayLength: null, maxStringLength: null })

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