Toml files are used for configuration settings.

This tutorial explains about following things.

  • Create a Node Project and add the required dependencies
  • Read toml file in javascript node code
  • Create and write toml file in NodeJS

Create a Nodejs Project

First, Create an empty directory in the terminal.

mkdir nodejs-toml-examples

Next, Change to the directory

cd nodejs-toml-examples

Next, Create a Node Project using the npm init command. This command creates a package.json with basic project settings.

E:\work\nodejs-toml-examples>npm init
This utility will walk you through creating a package.json file.
It only covers the most common items and tries to guess sensible defaults.

See `npm help init` for definitive documentation on these fields
and exactly what they do.

Use `npm install <pkg>` afterwards to install a package and
save it as a dependency in the package.json file.

Press ^C at any time to quit.
package name: (nodejs-toml-examples)
version: (1.0.0)
entry point: (index.js)
test command:
git repository:
license: (ISC)
About to write to E:\work\nodejs-toml-examples\package.json:

  "name": "nodejs-toml-examples",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  "author": "",
  "license": "ISC"

Is this OK? (yes)

Next, Create a src folder, that stores javascript files.

How to read toml file in Nodejs

Let’s create a config.toml file and copy the below content into it.



# mysql  host
host = "localhost:31016"

# mysql username
username = "root"

# mysql user password
password = "password"

# mysql database name
database = "students"

Node provides toml library to read and write files.

Install toml library in a project.

E:\work\nodejs-toml-examples> npm install toml

added 1 package, and audited 2 packages in 2s

Next, Create a read-toml.js file.

Here are steps to read toml file

  • Use fs and toml modules in a code. fs module is a node native module to read and write files
  • fs provides readFileSync function, takes a file name and encoding, It reads the file content into a variable.
  • Now, the variable holds the content of the file in the string format.
  • Convert string into a javascript object using toml.parse() function
  • You can access the data in the object using dot (.) notation.

Example to read the time file. read-toml.js:

const fs = require('fs');
const toml = require('toml');
// Read the TOML file into a string
const data = fs.readFileSync('config.toml', 'utf8');

// Parse the TOML data into a javascript object
const result = toml.parse(data);
} catch (e) {
  console.error("Parsing toml content on line " + e.line + ", column " + e.column +
    ": " + e.message);

Running the above code in the terminal outputs

E:\work\nodejs-toml-examples> node read-toml

How to write to toml file from an object in Node javascript

Following are steps to write to toml file

  • use fs and toml modules in a code
  • Create a JSOn object that holds key and value pairs
  • pass an object to toml.stringify() method, Convert the object toml format
  • Write to file using fs.writeFileSync() method takes a file name
  • toml file created on running the code
const fs = require('fs');
const toml = require('toml');

const obj = {
    mysql: {
      host: "localhost",
      username: "root",
      password: "password"

  // Convert the object to TOML format
  const str = toml.stringify(obj);

  // Create the TOML string to a file
  fs.writeFileSync('result.toml', str, 'utf8');

You can check source code for running code example.