How to Search and Explore Open Source Packages on Libraries.io

Updated

Libraries.io is a free service that indexes publicly available open source package information, and you can search it by license, language, or browse new, trending, and popular packages without an account for basic exploration. To use the full feature set and the API, you log in with a GitHub, GitLab, or Bitbucket account. The site currently monitors 11,927,330 packages across 32 package managers, so the practical challenge is narrowing that set to the dependencies that fit your project.

What you can do on Libraries.io

The platform collects package metadata scraped from the internet — it is not validated, corrected, or curated for accuracy. That matters for how you use it: treat results as a discovery and orientation tool, not as a verified source for compliance or risk decisions.

With that caveat in mind, the core capabilities are:

  • Search packages by license, language, or name.
  • Browse curated lists of new, trending, and popular packages.
  • Check metadata such as license, dependencies, and repository links.
  • Use the API for programmatic access, documented on the site.

Step-by-step: finding a package that fits your project

  1. Log in first if you need full functionality. Use GitHub, GitLab, or Bitbucket. Logging in means you accept the site's terms of service and privacy policy.
  2. Enter a search term. Start with the package name if you already know it, or a broader keyword if you are still exploring.
  3. Filter the results. Narrow by license (important if your project has license constraints) and by programming language to cut out irrelevant ecosystems.
  4. Open a package page. Check the license field, the source repository link, and the dependency information shown.
  5. Cross-check before committing. Because the data is scraped and unvalidated, confirm the license and version details at the package's own repository or registry before you add it to your build.
  6. Use the API for repeatable workflows. If you want to query packages programmatically — for example, to audit licenses across many dependencies — the API documentation on the site is the starting point.

Expected result: a shortlist of candidate packages with license and language already filtered, plus repository links you can verify at the source.

Browsing instead of searching

If you do not have a specific package in mind, the new, trending, and popular lists are useful for ecosystem awareness — seeing what is gaining adoption in a language you work in. This is closer to browsing a catalog than solving a specific dependency problem, so use it when you are scoping options rather than confirming a choice.

Libraries.io vs. the Tidelift Subscription

The site itself draws this distinction, and it is the most important decision point for anyone using the data for real work. Libraries.io data is scraped and not validated for accuracy. The Tidelift Subscription is a paid offering that provides curated, human-validated package data.

Dimension Libraries.io Tidelift Subscription
Package metadata Read from package and source repository metadata, not validated for accuracy Extensive and human-validated for accuracy
Secure development practices Not included Maintainers are paid to implement secure practices and provide attestations (e.g., 2FA status, security policy)
License data Read from package metadata, not validated Analyzed and manually validated, including normalized SPDX expressions
Dependency insights Limited, not validated Extensive, human-validated, including dependency graph relationships
Vulnerability insights Not included CVE data ingested from multiple sources, mapped to specific versions, plus maintainer CVE reviews

Choose Libraries.io if you are exploring, prototyping, or doing low-stakes discovery and can verify anything important yourself.

Consider the Tidelift Subscription if you are making important decisions about open source usage and management, need validated license data, or want vulnerability and maintenance signals such as end-of-life status and contributor security measures. Pricing is handled through Tidelift's own subscription pages — check there for current terms.

Common sticking points

  • Unvalidated data. The single biggest trap is treating a Libraries.io license field as authoritative. It is read from package metadata, not checked. Verify at the source.
  • No vulnerability data. If your goal is security review, Libraries.io alone will not cover it.
  • Login required for full use. Basic browsing is available, but plan on a GitHub, GitLab, or Bitbucket account for the complete experience and API access.
  • Scale can overwhelm. With nearly 12 million packages indexed, always filter by language and license before scanning results.