Metadata Checker API

Free Public API

Inspect Google SERP snippets, Twitter Cards, OpenGraph tags, and JSON-LD schema.

Try in Live Web Tool

POSThttps://api.headless-lender.com/api/v1/metadata

Public: No Key Needed•Highest Free Quota: 1,000 Req/Mo + 10h Browsers (No Card Required)

Overview & Architecture

Preview how your website appears on Google Search, Twitter/X, LinkedIn, and Facebook. Extract full meta tags, canonical links, robots directives, and schema markup in milliseconds.

Visual Google Search SERP card preview

Twitter/X Card & OpenGraph social share card preview

Full JSON-LD structured data extraction

Canonical URL and robots directive validation

Playwright Execution & Valkey Caching Pipeline

Because this endpoint utilizes full headless Chromium rendering, dynamic JavaScript and single-page apps (SPAs) are executed completely before conversion:

1. Cold Scrape (Cache MISS)~800ms – 2.5s

Chromium initializes, fetches the URL, executes client JavaScript, resolves DOM mutations, and generates output.

2. Repeat Request (Cache HIT)~5ms – 15ms

Returned instantly from Valkey/Redis cache with header X-Lender-Cache: HIT (15-minute TTL).

Code Integration Examples

Instant Public Endpoint: Zero configuration, no API key needed. Want our highest free quota? Get 1,000 free requests/month + 10 hours of cloud browsers with a free key (No credit card required).

curl -X POST https://api.headless-lender.com/api/v1/metadata \
  -H "Content-Type: application/json" \
  -d '{
    "url": "https://github.com"
  }'

Headers & Authentication Standard

1. Public Access (No Key)

No Authorization header required. Simply send a JSON POST request. Perfect for quick prototypes, small scripts, and low-volume scraping.

Content-Type: application/json

2. Free API Key (Highest Free Quota)

1,000 Req/Mo Free

Sign up in 10s with no credit card required. Unlocks 1,000 free monthly requests, 600 browser minutes (10 hours), 120 req/min burst limits, and cache-bypass controls.

Authorization: Bearer hl_live_your_api_key_here

Access Mode	Monthly Quota	Cloud Browser Time	Burst Limit	Credit Card	Action
Public Anonymous	Daily IP Allowance	5-min trial sandbox	10 req/min	None	Instant (No Setup)
Free Account (Highest Quota)	1,000 Req / Month	600 Mins (10 Hours)	120 req/min	Zero ($0 forever)	Claim Free Key →

Request Body Parameters

Field	Type	Required	Default	Description
url	string	required	—	Webpage URL to inspect.
waitUntil	'domcontentloaded' \| 'load' \| 'networkidle'	optional	'domcontentloaded'	Browser wait condition.

Response Schema & Example

200 OK — application/jsonDuration: ~800ms (Cold) / ~8ms (Cached)

{
  "url": "https://github.com",
  "title": "GitHub: Let's build from here · GitHub",
  "description": "GitHub is where over 100 million developers shape the future of software...",
  "canonical": "https://github.com",
  "openGraph": {
    "title": "GitHub: Let's build from here",
    "description": "GitHub is where over 100 million developers shape...",
    "image": "https://github.githubassets.com/images/modules/site/social-cards/campaign-social.png",
    "siteName": "GitHub",
    "type": "website"
  },
  "twitter": {
    "card": "summary_large_image",
    "site": "@github",
    "creator": "@github"
  },
  "jsonLd": [],
  "durationMs": 180
}

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