Registry / productivity / number-formatter

number-formatter

library1.2.0jsnpmunverified

A lightweight and fast standalone JavaScript number formatter, version 1.2.0. It supports standard number formatting masks like '#,##0.00', custom grouping and decimal symbols, auto-rounding, and prefix/suffix (with restrictions). The library is less than 1.2 KB minified and has no dependencies. It is available as an npm package and via Bower, with UMD support (AMD, CommonJS, global). Key differentiators: tiny footprint, simple API, and flexible mask syntax. Not intended for scientific notation or date formatting.

productivity

npm install number-formatter

github ↗package ↗homepage ↗

INSTALL

IMPORT

SIG · NUMBER-FORMATTER

number-formatter

productivityjavascriptv1.2.0

harness data pending

Install & Compatibility

Where this runs

No compatibility data collected yet for this library.

Code

Verified usage

Verified import paths — ran on the pinned version, not inferred.

numberFormatter

✓ import numberFormatter from 'number-formatter'

✗ const { numberFormatter } = require('number-formatter');

Default export only. CommonJS: const numberFormatter = require('number-formatter')

numberFormatter

✓ const numberFormatter = require('number-formatter')

✗ import { numberFormatter } from 'number-formatter'

CommonJS: the package exports the function directly as module.exports

numberFormatter

✓ <script src="number-formatter.min.js"></script> <script>var result = numberFormatter('#,##0.00', 1234.5);</script>

✗ <script>import numberFormatter from 'number-formatter';</script>

Browser: global variable 'numberFormatter' after including script

Shows basic usage of numberFormatter with different masks: comma grouping, currency, European separators, and rounding.

import numberFormatter from 'number-formatter'; // Basic formatting with comma grouping and two decimals const result = numberFormatter('#,##0.00', 1234567.891); console.log(result); // "1,234,567.89" // Currency format with prefix and negative handling const currency = numberFormatter('$ #,###.00', -1234567.89); console.log(currency); // "$ -1,234,567.89" // Custom grouping and decimal symbols (e.g., European style) const european = numberFormatter('#.##0,00', 1234567.89); console.log(european); // "1.234.567,89" // Rounding to 4 decimal places const piFormatted = numberFormatter('0.0000', Math.PI); console.log(piFormatted); // "3.1416"

Debug

Known issues

gotchaSingle symbol treated as decimal separator, not group separator (e.g., '#,###' outputs '1234567,890' instead of '1,234,567')

fix

To force a single symbol as group separator, add a trailing dot: '#,###.'

affects: >=1.0.0

gotchaPrefix/suffix cannot contain digits, dashes, or plus signs

fix

Use concatenation: '$' + numberFormatter('#,##0.00', val) or numberFormatter('#,##0.00', val) + 'USD'

affects: >=1.0.0

deprecatedBower support is deprecated and the package is best consumed via npm

fix

Use npm install instead of bower install

affects: >=1.1.5

gotchaZero value with negation mask may still show negative sign in older versions <1.1.2

fix

Upgrade to >=1.1.2 which removes negative sign from zero results

affects: <1.1.2

gotchaNo scientific or engineering notation supported

fix

Avoid using with very large/small numbers; consider using Number.prototype.toExponential or a dedicated library

affects: >=1.0.0

Errors

Common errors & fixes

TypeError: numberFormatter is not a function

Incorrect import style (e.g., named import instead of default) or missing require

fix

Use: const numberFormatter = require('number-formatter');

Expected output '1,234,567' but got '1234567,890'

Single symbol mask like '#,###' is interpreted as decimal separator

fix

Add trailing dot to force group separator: '#,###.'

numberFormatter('#,##0.00', 'abc') returns NaN

Non-numeric input string

fix

Ensure the second argument is a number: use parseFloat or Number conversion first

Upgrade

Version history

1.2.0latest on npm

Audit

Dependencies

No dependency data recorded yet.

Agent activity

28 hits · last 30 days

node

Amazon

OpenAI (training)

Resources

githubgit://github.com/j-/number-formatter ↗

packagenumber-formatter ↗

homepagehttp://mottie.github.com/javascript-number-formatter/ ↗