On-Page Instant API
Instant on-page SEO audit for any URL — meta tags, headings, schema, images, internal links, and Core Web Vitals. From $0.03/call.
Crawl and analyze any URL in real time. Returns title, meta description, headings structure, word count, internal/external links, images, page speed signals, and on-page SEO issues — all in a single call.
Try it live
Fill in the fields and hit Run to see a real response.
{
"ok": true,
"data": {
"url": "https://example.com",
"statusCode": 200,
"title": "Example Domain",
"metaDescription": "This is an example domain.",
"h1": [
"Example Domain"
],
"wordCount": 450,
"internalLinks": 12,
"externalLinks": 5,
"images": 3,
"imagesWithoutAlt": 1,
"loadTime": 1.2
}
}Features
One POST to /v1/seo/onpage/instant crawls a URL live and returns title, meta, headings, link counts, image stats, and load time together — no multi-step job to poll.
The response includes title, metaDescription, an h1 array, and wordCount, so you can flag missing tags, multiple H1s, or thin content directly from the JSON.
Each audit returns internalLinks and externalLinks counts, giving you the data to check link density and spot pages with no internal links.
The images and imagesWithoutAlt fields quantify accessibility and on-page issues, so you can surface pages that need alt-text fixes automatically.
A loadTime value (in seconds) plus statusCode let you catch slow or broken pages in the same call that audits their content.
Use cases
SEO Audit Automation
Feed URLs into automated audit pipelines and flag on-page issues like missing meta descriptions, broken headings, or thin content.
Content QA
Validate that every published page meets on-page SEO standards before or after launch.
Quick start
Copy this snippet and start making calls.
const res = await fetch('https://api.yepapi.com/v1/seo/onpage/instant', {
method: 'POST',
headers: {
'x-api-key': 'YOUR_API_KEY',
'Content-Type': 'application/json',
},
body: JSON.stringify({
"url": "https://example.com"
}),
});
const data = await res.json();
console.log(data);The on-page SEO API for developers — crawl any URL and get title, meta, headings & load time instantly
The On-Page Instant API crawls a single URL in real time and returns its on-page SEO data — title, meta description, H1s, word count, link counts, image stats, and load time — in one synchronous response. No queue, no callback: post a URL, get the audit.
It is the fast, single-page tool in YepAPI's on-page suite. For full Lighthouse scoring or deep content extraction, the Lighthouse and Content Parsing endpoints share the same key and URL-based interface.
What is an on-page SEO API?
An on-page SEO API fetches a web page and returns its SEO-relevant elements as structured data instead of a visual report. For a given URL you get the statusCode, title, metaDescription, the h1 array, wordCount, internalLinks and externalLinks counts, total images, imagesWithoutAlt, and loadTime — the exact signals an SEO checks by hand. That makes auditing automatable across thousands of pages. YepAPI delivers it at /v1/seo/onpage/instant: post one URL and receive the whole audit in a single immediate response, no crawl job to manage.
Build your own on-page audit tool
Wire the endpoint into a CMS pre-publish check that blocks a page lacking a meta description or running multiple H1s, using the title, metaDescription, and h1 array. Build a crawler that walks a sitemap and flags pages with thin wordCount, high imagesWithoutAlt, or slow loadTime. Because each call is synchronous, you can power an instant "audit this URL" box in a dashboard. Combine with the Content Parsing API when you need readability and keyword density beyond the structural checks here.
On-page SEO API pricing — $0.03/call
Each on-page audit is a flat $0.03 with no per-row add-on, since one call returns one page. Auditing a 1,000-page site costs about $30 end to end. The desktop tools and enterprise suites that produce this data charge for licenses or $0.15-per-call enterprise access; here it is a predictable three cents per page with no seat or subscription.
Audit on-page SEO at scale
Feed an entire sitemap through the endpoint to build a site-wide on-page report in one batch. The flat per-call price makes large crawls cost-predictable, and the structured fields let you compute aggregate health — percentage of pages missing meta descriptions, average wordCount, count of pages over a loadTime threshold. Store each run and diff against the last to catch regressions when a deploy strips a title tag or balloons page weight.
Try the on-page SEO API free
Start with $5 of free credit and no credit card — enough to audit well over a hundred URLs. Run it across a few of your own pages, confirm the title, meta, and image fields match what you see in the markup, and integrate the synchronous response into your pipeline before paying.
Start making API calls in 30 seconds
$5 free credit on signup. No credit card required. Pay per call.
What developers say
“Switched from SerpAPI and cut our SERP costs by 80%. Same data quality, way simpler billing.”
“One API key for AI models, SERP data, and web scraping. Saved us from managing 4 separate providers.”
“The $5 free credit let us prototype our entire rank tracking feature before committing. No other API does that.”
Frequently asked questions
Crawl and analyze any URL in real time. Returns title, meta description, headings structure, word count, internal/external links, images, page speed signals, and on-page SEO issues — all in a single call.
Each API call costs $0.03. No monthly minimums or subscriptions — you only pay for what you use.
Sign up for a free API key, then send a POST request to /v1/seo/onpage/instant. Check the code example above for a ready-to-use snippet in JavaScript, cURL, or Python.
YepAPI bundles SEO, AI, and web scraping APIs under one key with no monthly minimums. You get lower per-call pricing, a unified dashboard, and one billing account instead of managing multiple providers.
Ready to integrate?
Get your API key and start making calls in 30 seconds. $5 free credit on signup — no credit card required.
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