reading-time

Install the reading-time package using npm for your production environment.

npm install reading-time --production

You can use the readingTime function to estimate reading time from text.

Node.js usage: Import from the main entrypoint. Browser usage: Import from reading-time/lib/reading-time to avoid issues with the ReadingTimeStream class which is not supported in browsers without polyfills.

// In Node.js
const readingTime = require('reading-time');
// In the browser
const readingTime = require('reading-time/lib/reading-time');

const stats = readingTime(text);
// stats: { minutes: 1, time: 60000, words: { total: 200 } }
console.log(`The reading time is: ${stats.minutes} min`);

The ReadingTimeStream class allows you to process text via Node.js streams. You can pipe a readable stream into the analyzer and listen for the data event, which emits the word count.

const {ReadingTimeStream, readingTimeWithCount} = require('reading-time');
const fs = require('fs');

const analyzer = new ReadingTimeStream();
fs.createReadStream('foo')
  .pipe(analyzer)
  .on('data', (count) => {
    console.log(`The reading time is: ${readingTimeWithCount(count).minutes} min`);
  });

Returns an object representing the word count statistics for the provided text.

Parameters:

• text: The string to analyze.
• options (optional):
  • wordBound: A function returning a boolean to determine if a character is a word boundary (default: spaces, new lines, and tabs).

type WordCountStats = {
  total: number;
};

Calculates reading time statistics using pre-calculated word count stats. This is useful when working with streams or when you already have the word count.

Parameters:

• words: A WordCountStats object.
• options (optional):
  • wordsPerMinute: The average reading speed (default: 200).

Note: readingTime(text, options) === readingTimeWithCount(countWords(text, options), options).

Returns an object containing estimated reading time statistics based on the provided text.

Parameters:

• text: The string to analyze.
• options (optional):
  • wordsPerMinute: The average reading speed (default: 200).
  • wordBound: A function returning a boolean to determine if a character is a word boundary (default: spaces, new lines, and tabs).

type ReadingTimeResults = {
  minutes: number;
  time: number;
  words: WordCountStats;
};

Both readingTime, countWords, and readingTimeWithCount accept an optional Options object to customize the calculation:

• wordsPerMinute: (number) The assumed reading speed. Defaults to 200.
• wordBound: (function) A custom predicate function used to identify word boundaries (e.g., whitespace or newlines). By default, it uses isAnsiWordBound which checks for ' \n\r\t'.

The ReadingTimeStream class is a Node.js Transform stream (in objectMode) that processes text chunks to calculate cumulative word count statistics.

As chunks of text pass through the stream, it uses the underlying countWords logic to update an internal stats.total counter. When the stream is finished (during the _flush phase), it pushes a single WordCountStats object containing the total word count to the next stage of the pipeline.

To use it, pipe a text source (like a readable file stream) into ReadingTimeStream. The final output of the stream will be an object of type WordCountStats.