libphonenumber-js

libphonenumber-js is a free JavaScript and TypeScript library for developers adding personal phone-number handling to applications. It suits teams that want local parsing, formatting, and validation with control over shipped metadata. The strongest case is a smaller dependency than Google’s library; the weakest is its limited treatment of special numbers and extensions.

Overview

This is an open-source library released under MIT and Apache-2.0 licenses, intended for parsing and formatting personal phone numbers rather than providing a hosted lookup service. It runs through an API or in web applications, and can be installed with npm or loaded into a page with a script tag or npm CDN services such as unpkg and jsDelivr.

Key features

libphonenumber-js distinguishes a number that is possible by length from one whose digits satisfy current phone-number rules. That gives form developers a useful choice: length checks are less strict but less vulnerable to numbering-plan changes, while digit validation is more exact but can become stale as plans evolve.

The “As You Type” formatter parses both incomplete and complete input, making it suitable for a conventional phone field. Its input contract is narrow: it accepts digits and an initial plus sign, ignores other punctuation, and cannot accept extensions while the user types. Applications that need extension entry in the same interaction will need a different input design.

Text search can locate complete phone numbers, including numbers with extensions, which is useful for processing user-supplied text rather than only structured form fields. The library also offers line-type and reachability data, but no carrier data and no bulk-validation capability.

Metadata can be selected as min, max, mobile, or a custom set. This lets a team trade supported checks against bundle size instead of accepting one fixed payload. The full build is 145 kB, split into 65 kB of code and 80 kB of metadata, versus 550 kB for Google’s library. That is a meaningful reduction for browser bundles, provided the chosen metadata covers the application’s required countries and checks.

The scope is deliberately narrower than a complete telephone-information platform. Emergency numbers, short codes, alphabetic numbers, geolocation, and other special cases are outside its handling. React developers are directed to the separate react-phone-number-input project for a React phone-number component. Issues and behavior differences from Google’s library can be reported through GitHub or GitLab; GitLab is identified as the primary repository and GitHub as a backup.

Pricing

libphonenumber-js costs free under its sole free plan. It is an open-source JavaScript/TypeScript library with no paid tier, free trial, seat charge, quota, or renewal term stated. That makes it appropriate when validation runs inside your own application and you do not need a metered hosted API. It does not provide a paid upgrade for bulk validation, carrier data, or other service-level additions.

Platforms

The package is listed for API and web use. npm installation, browser script tags, and CDN delivery cover the web distribution paths described for the library.

Who it's for

Choose it for a development team building phone fields, parsers, or text-processing workflows that can keep metadata in the application and want a smaller JavaScript footprint. It is particularly suitable when free, local processing and configurable validation matter more than carrier intelligence or managed request capacity.

Look elsewhere if the product must validate large datasets in bulk, identify carriers, handle emergency or short numbers, provide geolocation, or accept extensions during live typing. Teams needing a ready-made React component should also evaluate the separate project recommended by the README.

Pros and cons

Pros

• Free open-source distribution: the library costs nothing and uses MIT and Apache-2.0 licenses.
• Configurable payload: min, max, mobile, and custom metadata let developers manage bundle size and checking coverage.
• Broad everyday handling: parsing, formatting, possibility checks, rule-based validation, live formatting, and text search cover common application workflows.
• Smaller full build: 145 kB is substantially below the 550 kB comparison for Google’s library.

Cons

• Narrow special-number scope: emergency numbers, short codes, alphabetic numbers, geolocation, and other special cases are not handled.
• Validation can age: strict digit checks depend on numbering rules that change, so length-only validation may be safer for some uses.
• Typing limitations: punctuation is ignored and extensions cannot be entered in the “As You Type” formatter.
• No carrier or bulk service: carrier data and bulk validation are absent, so data-enrichment or batch workloads need another tool.

Alternatives

For a broader directory of options, see Phone Number Validation Software.

Accessibility Test Framework for Android is a free Android-focused framework rather than a phone-number library, so choose it for accessibility testing.

Abstract Email Validation API is a freemium API for email validation, with paid request plans, and is the better fit for email-focused checks.

IPQualityScore Phone Validation API is a freemium API with a free trial and hosted lookup pricing, suited to teams wanting an external phone-validation service.

numlookupapi.com offers freemium hosted plans with request quotas and batch validation, making it a choice for API-driven workloads.

PhoneValidationAPI is a freemium API with monthly request plans for teams that prefer managed validation.

Veriphone is a freemium API with a free trial, carrier and line-type data, bulk CSV support, and monthly validation credits.

Neutrino Phone Validate is a freemium API with a limited free account and paid request tiers.

Numverify is a freemium API from APILayer with a free trial and paid request plans.

Verdict

libphonenumber-js is the right choice for developers who need free, in-application handling of ordinary personal numbers and want to keep browser payloads under control. Choose it for its local toolkit and metadata flexibility; look elsewhere when special numbers, extensions during typing, carrier data, or bulk and hosted validation are core requirements.