@power-seo/core

@power-seo/core — Framework-Agnostic SEO Utilities for TypeScript & React

Zero-dependency foundation for the @power-seo toolkit. Provides shared types, meta tag builders, URL utilities, text statistics, keyword density analysis, robots directive builder, validators, and constants.

The foundation package used by all other @power-seo packages. Useful on its own for headless SEO tooling, custom framework integrations, or any Node.js application that needs SEO utilities without a React dependency.

Documentation

• Package docs: apps/docs/src/content/docs/packages/core.mdx
• Ecosystem overview: README.md
• Contributing guide: CONTRIBUTING.md

Features

• Meta tag builders — generate typed MetaTag[] and LinkTag[] objects for title, description, Open Graph, Twitter Card, hreflang
• Robots directive builder — build and parse robots meta content strings with full directive support (noindex, nofollow, max-snippet, max-image-preview, max-video-preview, unavailable_after, noarchive, nosnippet, noimageindex, notranslate)
• Title template engine — %s | Site Name style templates with applyTitleTemplate()
• Meta validators — validate title and description length in both characters and pixel width
• URL utilities — normalize, slug-ify, strip tracking params, resolve canonical, check absolute/relative
• Text statistics — word count, sentence count, syllable count, paragraph count from HTML content
• Keyword density analysis — calculate density, count occurrences, analyze keyphrase distribution
• Shared constants — TITLE_MAX_LENGTH, META_DESCRIPTION_MAX_LENGTH, OG_IMAGE, KEYWORD_DENSITY thresholds
• Zero runtime dependencies — safe to use in any environment including edge runtimes
• Dual ESM + CJS — works with any bundler or Node.js require
• TypeScript-first — all types exported, full .d.ts declarations

Table of Contents

• Installation
• Quick Start
• Usage
  • Meta Tag Builders
  • Robots Directive Builder
  • Title Template Engine
  • Meta Validators
  • URL Utilities
  • Text Statistics
  • Keyword Density
  • Constants
• API Reference
• The @power-seo Ecosystem
• About CyberCraft Bangladesh

Installation

npm install @power-seo/core

yarn add @power-seo/core

pnpm add @power-seo/core

Quick Start

import { buildMetaTags, buildRobotsContent, validateTitle, toSlug } from '@power-seo/core';

const tags = buildMetaTags({
  title: 'My Page',
  description: 'Page description',
  robots: { index: true, follow: true },
});
const robots = buildRobotsContent({ index: false, maxSnippet: 150 }); // → "noindex, max-snippet:150"
const valid = validateTitle('My Page Title'); // { valid: true, length: 14, pixelWidth: 95 }
const slug = toSlug('My Blog Post!'); // → "my-blog-post"

Usage

Meta Tag Builders

import {
  buildMetaTags,
  buildLinkTags,
  buildOpenGraphTags,
  buildTwitterTags,
  buildHreflangTags,
} from '@power-seo/core';

const meta = buildMetaTags({
  title: 'My Page',
  description: 'Page description',
  robots: { index: true, follow: true },
});

const links = buildLinkTags({ canonical: 'https://example.com/page' });

const og = buildOpenGraphTags({
  title: 'My Page',
  description: 'Page description',
  type: 'website',
  url: 'https://example.com',
  images: [{ url: 'https://example.com/og.jpg', width: 1200, height: 630 }],
});

const twitter = buildTwitterTags({
  card: 'summary_large_image',
  site: '@mysite',
  title: 'My Page',
  description: 'Page description',
  image: 'https://example.com/twitter.jpg',
});

const hreflang = buildHreflangTags([
  { hrefLang: 'en', href: 'https://example.com/page' },
  { hrefLang: 'fr', href: 'https://fr.example.com/page' },
  { hrefLang: 'x-default', href: 'https://example.com/page' },
]);

Robots Directive Builder

import { buildRobotsContent, parseRobotsContent } from '@power-seo/core';

// Build robots meta content string
buildRobotsContent({ index: true, follow: true });
// → "index, follow"

buildRobotsContent({ index: false, follow: false, noarchive: true });
// → "noindex, nofollow, noarchive"

buildRobotsContent({ index: true, maxSnippet: 150, maxImagePreview: 'large' });
// → "index, max-snippet:150, max-image-preview:large"

// Parse existing robots string back to config
parseRobotsContent('noindex, follow, max-image-preview:large');
// → { index: false, follow: true, maxImagePreview: 'large' }

All supported directives:

Directive	Type	Description
index	boolean	true → index, false → noindex
follow	boolean	true → follow, false → nofollow
noarchive	boolean	Prevent cached version in search results
nosnippet	boolean	Prevent text/video snippet in results
noimageindex	boolean	Prevent page images from being indexed
notranslate	boolean	Prevent Google Translate offer
maxSnippet	number	Max text snippet length (e.g. 150)
maxImagePreview	'none' | 'standard' | 'large'	Max image preview size
maxVideoPreview	number	Max video preview duration in seconds
unavailableAfter	string	Date after which to remove page from results

Title Template Engine

import { applyTitleTemplate, createTitleTemplate } from '@power-seo/core';

applyTitleTemplate('Blog Post', '%s | My Site');
// → "Blog Post | My Site"

const template = createTitleTemplate({ separator: '|', suffix: 'My Site' });
template.apply('Blog Post'); // → "Blog Post | My Site"

Meta Validators

import { validateTitle, validateMetaDescription, calculatePixelWidth } from '@power-seo/core';

validateTitle('My Page Title');
// { valid: true, length: 14, pixelWidth: 95, warnings: [] }

validateMetaDescription('A description of the page content for search engines.');
// { valid: true, length: 53, pixelWidth: 340, warnings: [] }

calculatePixelWidth('My Title'); // → 56

URL Utilities

import {
  normalizeUrl,
  toSlug,
  stripTrackingParams,
  ensureTrailingSlash,
  removeTrailingSlash,
  isAbsoluteUrl,
  resolveCanonical,
} from '@power-seo/core';

normalizeUrl('https://example.com/PATH?utm_source=x'); // → "https://example.com/path"
toSlug('My Blog Post!'); // → "my-blog-post"
stripTrackingParams('https://example.com?utm_source=google&page=1'); // → "https://example.com?page=1"
ensureTrailingSlash('https://example.com/blog'); // → "https://example.com/blog/"
removeTrailingSlash('https://example.com/blog/'); // → "https://example.com/blog"
isAbsoluteUrl('https://example.com'); // → true
isAbsoluteUrl('/relative/path'); // → false

Text Statistics

import {
  getTextStatistics,
  stripHtml,
  getWords,
  getSentences,
  countSyllables,
} from '@power-seo/core';

const stats = getTextStatistics(
  '<h1>Hello</h1><p>This is a sample paragraph with several words.</p>',
);
// { wordCount: 9, sentenceCount: 1, paragraphCount: 1, syllableCount: 14, avgWordsPerSentence: 9 }

stripHtml('<p>Hello <strong>world</strong></p>'); // → "Hello world"
getWords('Hello world'); // → ["Hello", "world"]
countSyllables('beautiful'); // → 3

Keyword Density

import {
  calculateKeywordDensity,
  countKeywordOccurrences,
  analyzeKeyphraseOccurrences,
} from '@power-seo/core';

calculateKeywordDensity('react seo is great for react apps', 'react'); // → 0.1667 (16.67%)
countKeywordOccurrences('react seo is great for react apps', 'react'); // → 2

const analysis = analyzeKeyphraseOccurrences(
  'Best coffee shops in NYC. The coffee shops on Fifth Avenue are particularly good.',
  'coffee shops',
);
// { count: 2, density: 0.1538, positions: [1, 7], distribution: 'good' }

Constants

import {
  TITLE_MAX_LENGTH,
  META_DESCRIPTION_MAX_LENGTH,
  OG_IMAGE,
  KEYWORD_DENSITY,
  READABILITY,
} from '@power-seo/core';

TITLE_MAX_LENGTH; // 60
META_DESCRIPTION_MAX_LENGTH; // 158
OG_IMAGE.MIN_WIDTH; // 1200
OG_IMAGE.MIN_HEIGHT; // 630
KEYWORD_DENSITY.MIN; // 0.005 (0.5%)
KEYWORD_DENSITY.MAX; // 0.03  (3%)

API Reference

Meta Builders

Function	Signature	Description
buildMetaTags	(config: MetaConfig) => MetaTag[]	Generate meta tag objects from SEO config
buildLinkTags	(config: LinkConfig) => LinkTag[]	Generate link tag objects (canonical, alternate)
buildOpenGraphTags	(config: OpenGraphConfig) => MetaTag[]	Generate Open Graph og:* meta tags
buildTwitterTags	(config: TwitterConfig) => MetaTag[]	Generate Twitter Card twitter:* meta tags
buildHreflangTags	(entries: HreflangEntry[]) => LinkTag[]	Generate hreflang <link rel="alternate"> tags
resolveTitle	(title: string, template?: string) => string	Resolve title with optional template

Robots

Function	Signature	Description
buildRobotsContent	(directive: RobotsDirective) => string	Build robots meta content string
parseRobotsContent	(content: string) => RobotsDirective	Parse robots string into RobotsDirective

Title

Function	Signature	Description
applyTitleTemplate	(title: string, template: string) => string	Apply %s template to title
createTitleTemplate	(options: TitleTemplateOptions) => TitleTemplate	Create reusable title template

Validators

Function	Signature	Description
validateTitle	(title: string) => ValidationResult	Validate title length and pixel width
validateMetaDescription	(description: string) => ValidationResult	Validate description length and pixel width
calculatePixelWidth	(text: string) => number	Calculate pixel width using Google's character width table

URL Utilities

Function	Signature	Description
resolveCanonical	(url: string, base: string) => string	Resolve canonical URL against base
normalizeUrl	(url: string) => string	Normalize URL (lowercase, remove trailing slash)
ensureTrailingSlash	(url: string) => string	Add trailing slash if missing
removeTrailingSlash	(url: string) => string	Remove trailing slash if present
stripQueryParams	(url: string) => string	Remove all query parameters
stripTrackingParams	(url: string) => string	Remove UTM and tracking parameters only
isAbsoluteUrl	(url: string) => boolean	Check if URL is absolute
toSlug	(text: string) => string	Convert text to URL-safe slug

Text Statistics

Function	Signature	Description
getTextStatistics	(html: string) => TextStatistics	Comprehensive text statistics from HTML
stripHtml	(html: string) => string	Remove HTML tags
getWords	(text: string) => string[]	Split into words array
getSentences	(text: string) => string[]	Split into sentences array
getParagraphs	(text: string) => string[]	Split into paragraphs array
countSyllables	(word: string) => number	Count syllables in a single word

Keyword Analysis

Function	Signature	Description
calculateKeywordDensity	(text: string, keyword: string) => number	Keyword density as decimal (0.05 = 5%)
countKeywordOccurrences	(text: string, keyword: string) => number	Raw occurrence count
analyzeKeyphraseOccurrences	(text: string, keyphrase: string) => KeyphraseAnalysis	Detailed keyphrase analysis

Core Types

Type	Description
MetaTag	{ name?: string; property?: string; content: string; httpEquiv?: string }
LinkTag	{ rel: string; href: string; hrefLang?: string; type?: string }
RobotsDirective	Full robots directive configuration object
MetaConfig	Input config for buildMetaTags()
OpenGraphConfig	Input config for buildOpenGraphTags()
TwitterConfig	Input config for buildTwitterTags()
ValidationResult	{ valid: boolean; length: number; pixelWidth: number; warnings: string[] }
TextStatistics	{ wordCount: number; sentenceCount: number; paragraphCount: number; syllableCount: number; avgWordsPerSentence: number }

The @power-seo Ecosystem

All 17 packages are independently installable — use only what you need.

Package	Install	Description
@power-seo/core	npm i @power-seo/core	Framework-agnostic utilities, types, validators, and constants
@power-seo/react	npm i @power-seo/react	React SEO components — meta, Open Graph, Twitter Card, robots, breadcrumbs
@power-seo/meta	npm i @power-seo/meta	SSR meta helpers for Next.js App Router, Remix v2, and generic SSR
@power-seo/schema	npm i @power-seo/schema	Type-safe JSON-LD structured data — 20 builders + 18 React components
@power-seo/content-analysis	npm i @power-seo/content-analysis	Yoast-style SEO content scoring engine with React components
@power-seo/readability	npm i @power-seo/readability	Readability scoring — Flesch-Kincaid, Gunning Fog, Coleman-Liau, ARI
@power-seo/preview	npm i @power-seo/preview	SERP, Open Graph, and Twitter/X Card preview generators
@power-seo/sitemap	npm i @power-seo/sitemap	XML sitemap generation, streaming, index splitting, and validation
@power-seo/redirects	npm i @power-seo/redirects	Redirect engine with Next.js, Remix, and Express adapters
@power-seo/links	npm i @power-seo/links	Link graph analysis — orphan detection, suggestions, equity scoring
@power-seo/audit	npm i @power-seo/audit	Full SEO audit engine — meta, content, structure, performance rules
@power-seo/images	npm i @power-seo/images	Image SEO — alt text, lazy loading, format analysis, image sitemaps
@power-seo/ai	npm i @power-seo/ai	LLM-agnostic AI prompt templates and parsers for SEO tasks
@power-seo/analytics	npm i @power-seo/analytics	Merge GSC + audit data, trend analysis, ranking insights, dashboard
@power-seo/search-console	npm i @power-seo/search-console	Google Search Console API — OAuth2, service account, URL inspection
@power-seo/integrations	npm i @power-seo/integrations	Semrush and Ahrefs API clients with rate limiting and pagination
@power-seo/tracking	npm i @power-seo/tracking	GA4, Clarity, PostHog, Plausible, Fathom — scripts + consent management

About CyberCraft Bangladesh

CyberCraft Bangladesh is a Bangladesh-based enterprise-grade software engineering company specializing in ERP system development, AI-powered SaaS and business applications, full-stack SEO services, custom website development, and scalable eCommerce platforms. We design and develop intelligent, automation-driven SaaS and enterprise solutions that help startups, SMEs, NGOs, educational institutes, and large organizations streamline operations, enhance digital visibility, and accelerate growth through modern cloud-native technologies.

Website	ccbd.dev
GitHub	github.com/cybercraftbd
npm Organization	npmjs.com/org/power-seo
Email	[e-mail]

© 2026 CyberCraft Bangladesh · Released under the MIT License