Check if your npm package name is actually publishable.
Tests against npm's undocumented similarity filter, not just the registry.

The Problem

You check if a package name is available on npm. It says yes. You build the whole thing. You run npm publish. Boom:

403 Package name too similar to existing packages degit,pdfkit,exit

npm has an undocumented similarity filter that blocks names even if they don't exist on the registry. npm publish --dry-run doesn't catch it either. Neither does npm-name-cli.

can-i-publish actually tests publishability by checking both the registry AND the similarity filter.

Note

Similarity filter testing requires npm login. Without it, registry and squatter checks still work.

npm-name-cli vs can-i-publish

Try it yourself — check dxkit, a name that looks available but is actually blocked:

# npm-name-cli says it's available (wrong — will fail on npm publish)
$ npx npm-name-cli dxkit
✔ dxkit is available

# can-i-publish catches the similarity block
$ npx can-i-publish dxkit
⚠ dxkit is blocked by npm similarity filter
  Similar to: degit, pdfkit, exit

Other names you can verify: reacto, expresss, loadash, chulk.

	npm-name-cli	can-i-publish
Registry check	Yes	Yes
Organization check (@org)	Yes	Yes
Squatter detection	Yes	Yes
Similarity filter	No	Yes
Catches dxkit as blocked	No	Yes
Shows similar packages	No	Yes
Suggests alternatives	No	Yes (--suggest)

Install

npx can-i-publish my-package

Or install globally:

npm install -g can-i-publish

Usage

# Check a single name
can-i-publish my-package

# Check multiple names at once
can-i-publish my-tool my-lib my-app

# Check an organization name
can-i-publish @my-org

# Get suggestions if blocked
can-i-publish dxkit --suggest

# JSON output (for scripting)
can-i-publish my-package --json

Output

$ can-i-publish abc123 chalk dxkit my-cool-tool @ava

⚠ abc123 is squatted (https://www.npmjs.com/package/abc123)
✖ chalk is unavailable (https://www.npmjs.com/package/chalk)
⚠ dxkit is blocked by npm similarity filter
  Similar to: degit, pdfkit, exit
✔ my-cool-tool is available
✖ @ava is unavailable (https://www.npmjs.com/org/ava)

How It Works

1. Validates the name against npm naming rules (lowercase, no spaces, under 214 chars)
2. Checks the registry to see if the package already exists
3. Detects squatters — flags packages that exist but appear abandoned (low downloads, no readme, no prod version)
4. Tests the similarity filter by attempting a publish probe against the npm registry using your npm credentials

Options

Flag	Description
-s, --suggest	Suggest alternative names if unavailable
-j, --json	Output results as JSON
-V, --version	Show version
-h, --help	Show help

Exit Codes

• 0 — all names are available or squatted
• 1 — one or more names are unavailable, blocked, or invalid

Useful for CI/scripting:

can-i-publish my-package && npm publish

Programmatic API

import { checkName, suggestNames } from 'can-i-publish';

const result = await checkName({ name: 'my-package' });
// { name, status: 'available' | 'taken' | 'squatted' | 'blocked' | 'invalid', reason?, similarTo? }

const suggestions = await suggestNames({ name: 'dxkit', limit: 5 });
// [{ name: 'dxkit-cli', status: 'available' }, ...]

Credits

Inspired by npm-name-cli by Sindre Sorhus.

License

MIT

---

Built with commandcode by @saqibameen