Faker.js

Open Source

Generate massive amounts of realistic fake data — names, emails, addresses, finance, lorem, and more.

Visit website GitHub

Pricing

Free / Open source

Type

Automation

Languages

JavaScript, TypeScript

// VERDICT

Reach for Faker.js when you want realistic, varied fake data for JS/TS tests and seeding. Skip it when you need deterministic fixed datasets, highly domain-specific data, or are in another language (use that language's Faker).

Best for

Generating realistic fake data for tests and development - names, addresses, emails, dates and more, so tests use varied, lifelike data instead of brittle hard-coded values.

Avoid when

You need deterministic fixed datasets, domain-specific data a generic faker can't produce, or a non-JS stack (use a port).

CI/CD fit

Library in tests/seeders · seeded for reproducibility

Languages

JavaScript · TypeScript

Team fit

JS/TS teams · Test-data generation · Seeding dev/test environments

Setup

Easy

Maintenance

Low

Learning

Beginner

Licence

Free / Open source

// BEST FOR

Generating realistic names, addresses, emails, dates, etc.
Varied test data instead of brittle hard-coded values
Seeding development and test databases
Reproducible data via a fixed seed
Reducing test coupling to specific values
Quick, expressive data generation

// AVOID WHEN

You need deterministic fixed datasets
Highly domain-specific data is required
Your stack isn't JS (use a Faker port)
Exact known values are needed for assertions
Data must follow strict business rules
Minimal dependencies are mandated

// QUICK START

npm install -D @faker-js/faker
// faker.seed(123); faker.person.fullName(); faker.internet.email();

// ALTERNATIVES TO CONSIDER

Tool	Choose it when
Chance.js	You want another JS random-data generator.
DbUnit	You want fixed datasets for DB tests instead of random data.

// FEATURES

70+ data categories (person, internet, finance, lorem, etc.)
70+ locales for region-specific fixtures
Seedable RNG for deterministic test data
Tree-shakeable modular imports
TypeScript types out of the box

// PROS

Vast catalogue of realistic generators
Seed-based determinism makes tests reproducible
Strong locale support for i18n testing
Active community-led development

// CONS

Bundle size if imported wholesale
Original `faker` package was sabotaged in 2022 — community fork is the canonical one now
Not a mocking library on its own — pair with MSW or similar