SEO Quick Validator API

POST

Catch on-page SEO issues and missing tags across any web page.

SEO Quick Validator inspects live web pages for on-page SEO errors and tag issues. Pass any URL to inspect title lengths, meta descriptions, H1 headings, viewport and canonical tags, image alt text, and unverified external links.

Try it — live request, no key required

Request

POSTapi.apiverve.com/v1/seovalidator

Body

urlstring

Verification

Format

No key required to try it. Get a key to use it in your app.

Example

{
  "status": "ok",
  "error": null,
  "data": {
    "url": "https://apiverve.com",
    "passed": false,
    "issueCount": 6,
    "issues": [
      "Image missing 'alt' attribute: '/assets/img/hero-diagram.png'",
      "Image missing 'alt' attribute: '/assets/img/logo-mark.svg'",
      "External link missing 'rel' attribute: 'https://twitter.com/apiverve'",
      "External link missing 'rel' attribute: 'https://github.com/apiverve'",
      "External link missing 'rel' attribute: 'https://status.apiverve.com'",
      "Missing meta 'keywords' tag in head"
    ],
    "checks": {
      "hasTitle": true,
      "titleLength": 54,
      "hasMetaDescription": true,
      "metaDescriptionLength": 158,
      "hasMetaKeywords": false,
      "h1Count": 1,
      "hasCanonical": true,
      "hasViewport": true,
      "imagesTotal": 8,
      "imagesMissingAlt": 2,
      "externalLinksTotal": 10,
      "externalLinksMissingRel": 3
    },
    "seoScore": 93,
    "grade": "A"
  }
}

About the SEO Quick Validator API

SEO Validator works by fetching and parsing a web page, then evaluating its on-page SEO signals — title, meta description, H1 structure, canonical link, mobile viewport, image alt text and external-link rel attributes. It returns each check as a structured field, a list of issues to fix, and a weighted 0-100 score with an A–F grade so you can gauge a page's SEO health at a glance.

What people use it for

CMS Publishing Check: Before publishing a blog post, CMS editors verify that title tags, meta descriptions, and image alt text meet basic standards.
Staging Site Audits: When deploying a site update, QA engineers test generated landing pages to catch missing canonical tags and duplicate H1 headings.
Agency Client Onboarding: Marketing agencies inspect client websites to list total issue counts and flag external links lacking security rel attributes.
Ecommerce Catalog Monitoring: To keep product catalogs discoverable, ecommerce platforms scan merchant pages to detect missing image descriptions and absent viewport configurations.

Ways to call it

One endpoint, many ways in — REST with JSON, XML, YAML and CSV, plus GraphQL and an MCP interface for AI agents.

JSON: Default REST response
XML: Markup format
YAML: Human-readable
CSV: Tabular export
GraphQL: Query language
MCP: For AI agents

View all integrations →

Other ways to use SEO Quick Validator

Same data, same APIVerve account, same credit balance — one key works on all of them.

Give it to an AI agentConnect over MCP and your agent calls it as a native tool — Claude, Cursor, ChatGPT.on VerveKit Google Sheets or ExcelA =VERVE() formula fills a column — no script, no export, recalculates in place.on VerveSheets Ground an agent on itA cited, machine-checkable fact your model can't produce on its own.on VerveContext

Questions.

Common questions about the SEO Quick Validator API.

Read the docs →

What on-page SEO signals does the validator check?

It evaluates core on-page elements including title tag presence and length, meta description presence and length, meta keywords, H1 tag count, and canonical link tags. It also checks for mobile viewport meta tags, counts images missing alt text, and flags external links missing rel attributes.

Do I get the composite SEO score and letter grade on the Free plan?

No, the 0-100 SEO health score and A through F letter grade are premium fields. Any paid subscription unlocks them, starting with Starter. The Free plan returns the pass status, issue count, issue list, and the raw rule check breakdown.

How many page validations does the Free plan cover?

The Free plan gives you 200 monthly credits, which covers 20 page validations at 10 credits each. If you need higher volume, the Starter plan covers up to 20,000 page validations per month, which works out to about $0.0015 per check or $1.50 per 1,000 calls.

Does the validator evaluate live web pages in real time?

Yes, SEO Quick Validator fetches and parses the live web page directly when you make the call. It evaluates the current HTML markup on demand rather than pulling from an outdated or cached database.

What values are returned if a page is missing a title or meta description?

When an element is absent, its corresponding boolean check returns false and its character length field returns null. The omission is also flagged inside the issues array and included in the total issue count.

Can I display these SEO audit results inside my own client dashboard?

Yes, commercial use is allowed on any paid plan. You can integrate the checks, issues, and grades into your own client reports or SaaS platform, provided you do not resell or redistribute the raw API data as-is.

Request parameters — POST /v1/seovalidator

Sent as JSON in the request body. Premium parameters are accepted on every plan but only take effect on plans that include them. Anything not listed here is dropped rather than passed through.

Required

Parameter	Type	Example	Description
`url`Required	string	`https://www.example.com`	The URL of the web page to validate the SEO metrics of url

Example request

curl -X POST "https://api.apiverve.com/v1/seovalidator" \
  -H "x-api-key: YOUR_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"url":"https://apiverve.com"}'

Authentication

Send your key in the x-api-key header. That is the only auth step — no token exchange, and no per-endpoint scope to configure.

Header	When	Value
`x-api-key`Required	Every request	Your API key. Header names are case-insensitive, so `X-API-Key` is the same header.
`Authorization`Alternate	Instead of the above	`Bearer <key>` — for clients that only expose bearer auth. Resolves to the same account and the same billing.
`content-type`Required	POST body	`application/json`

401 is the only auth verdict

A 401 means the key is missing, invalid or expired. A 403 means the key is valid but not permitted here — blocked by a key restriction or an IP allow-list. Running out of credits is a 429.

Response — POST /v1/seovalidator

Every APIVerve endpoint returns the same three top-level keys, so one response handler covers your whole integration: status, error and data. Only data changes shape.

Sample response

{
  "status": "ok",
  "error": null,
  "data": {
    "url": "https://apiverve.com",
    "passed": false,
    "issueCount": 6,
    "issues": [
      "Image missing 'alt' attribute: '/assets/img/hero-diagram.png'",
      "Image missing 'alt' attribute: '/assets/img/logo-mark.svg'",
      "External link missing 'rel' attribute: 'https://twitter.com/apiverve'",
      "External link missing 'rel' attribute: 'https://github.com/apiverve'",
      "External link missing 'rel' attribute: 'https://status.apiverve.com'",
      "Missing meta 'keywords' tag in head"
    ],
    "checks": {
      "hasTitle": true,
      "titleLength": 54,
      "hasMetaDescription": true,
      "metaDescriptionLength": 158,
      "hasMetaKeywords": false,
      "h1Count": 1,
      "hasCanonical": true,
      "hasViewport": true,
      "imagesTotal": 8,
      "imagesMissingAlt": 2,
      "externalLinksTotal": 10,
      "externalLinksMissingRel": 3
    },
    "seoScore": 93,
    "grade": "A"
  }
}

Response fields

Paths are relative to data. Premium fields are absent rather than zeroed on plans that do not include them, so check for presence instead of comparing to 0.

Field	Type	Example	Description
`url`	string	`"https://apiverve.com"`	The validated URL that was analyzed for SEO issues
`passed`	boolean	`false`	Whether the URL passed all SEO validation checks
`issueCount`	number	`6`	Total number of SEO issues found on the page
`issues`	array	`[Image missing 'alt' attribute: '/assets/img/hero-diagram.png', ...]`	Array of SEO issues found (missing alt tags, missing meta tags, multiple H1s, etc.)
`checks`	object	`{...}`	Structured per-rule breakdown of the on-page SEO signals behind the issue list, exposed as booleans, counts and lengths
`hasTitle`	boolean	`true`	Whether the page has a non-empty <title> tag in the head
`titleLength`	number	`54`	Character length of the title (null when absent); ~50-60 characters is the common recommendation
`hasMetaDescription`	boolean	`true`	Whether the page has a meta description tag
`metaDescriptionLength`	number	`158`	Character length of the meta description (null when absent); ~150-160 characters is the common recommendation
`hasMetaKeywords`	boolean	`false`	Whether a meta keywords tag is present (largely deprecated for ranking)
`h1Count`	number	`1`	Number of H1 tags on the page; exactly one is recommended
`hasCanonical`	boolean	`true`	Whether the page declares a canonical link tag
`hasViewport`	boolean	`true`	Whether the page declares a mobile viewport meta tag
`imagesTotal`	number	`8`	Total number of <img> elements on the page
`imagesMissingAlt`	number	`2`	Number of images missing an alt attribute
`externalLinksTotal`	number	`10`	Total number of external (http/https) links on the page
`externalLinksMissingRel`	number	`3`	Number of external links missing a rel attribute
`seoScore`Premium	number	`93`	Composite 0-100 on-page SEO health score, weighted by real ranking impact (title, meta description and H1 weigh most; image-alt and link-rel penalties scale with the proportion of elements affected). Higher is better
`grade`Premium	string	`"A"`	Letter grade derived from the score: A (90+), B (80+), C (70+), D (60+) or F

Response headers

Every response carries your balance, so your own code always knows where it stands without polling anything. All four are exposed to browsers through CORS.

Header	What it carries
`x-api-remaining-credits`	Credits left in the current cycle
`x-api-credits-used`	Credits spent in the current cycle
`x-api-max-credits`	The allowance for the cycle
`x-api-version`	Version of the endpoint that answered

Errors

Read the HTTP status first, then error for the specific reason. The body names the parameter that has to change.

Status	Meaning	What to do
`400`	Input was rejected	Read `error`; it names the parameter that has to change.
`401`	Key missing or invalid	Check the header name and the key value.
`403`	Key valid, but not permitted here	A key restriction or an IP allow-list — never a bad key.
`429`	Rate limited, or out of credits	Read `error` to tell them apart, then back off or top up.

What a call costs — 10 credits per call

Credits are shared across every APIVerve API — one balance, one key, one bill. Failed requests never count against it, so a rejected input costs nothing.

Plan	Per month	Credits	SEO Quick Validator calls	Per 1,000 calls
Free	Free	200	20	Free
Starter	$29.99	200,000	20,000	$1.50
Pro	$99.99	1,000,000	100,000	$1.00
Mega	$299.99	4,000,000	400,000	$0.75

Calls are what the credits buy at this API's rate — spend them here, on any of the other APIs, or across both. Nothing is reserved per endpoint.

Compare all pricing tiers →

Call it from cURL — POST /v1/seovalidator

No SDK to install — this is a plain HTTPS call to /v1/seovalidator with your key in the x-api-key header. Swap in a real key and it runs as-is.

cURL

1
2

curl "https://api.apiverve.com/v1/seovalidator" \
  -H "x-api-key: YOUR_API_KEY"

Resources

GitHubapiverve/seovalidator-apiSource, issues and the examples this page is built from.ReferenceSEO Quick Validator API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/seovalidatornpm apiverve-seovalidatorPyPI APIVerve.API.SEOValidatorNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Node.js — POST /v1/seovalidator

Install the Node.js SDK, then call the SEO Quick Validator API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — npm

npm install @apiverve/seovalidator

Node.js

const res = await fetch("https://api.apiverve.com/v1/seovalidator", {
  headers: { "x-api-key": "YOUR_API_KEY" },
});
const { data } = await res.json();
console.log(data);

Resources

npm@apiverve/seovalidatorThe published Node.js client, versioned and signed.GitHubapiverve/seovalidator-apiSource, issues and the examples this page is built from.ReferenceSEO Quick Validator API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

apiverve-seovalidatorPyPI APIVerve.API.SEOValidatorNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Python — POST /v1/seovalidator

Install the Python SDK, then call the SEO Quick Validator API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — PyPI

pip install apiverve-seovalidator

Python

import requests

res = requests.get(
    "https://api.apiverve.com/v1/seovalidator",
    headers={"x-api-key": "YOUR_API_KEY"},
)
print(res.json()["data"])

Resources

PyPIapiverve-seovalidatorThe published Python client, versioned and signed.GitHubapiverve/seovalidator-apiSource, issues and the examples this page is built from.ReferenceSEO Quick Validator API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/seovalidatornpm APIVerve.API.SEOValidatorNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from C# / .NET — POST /v1/seovalidator

Install the C# / .NET SDK, then call the SEO Quick Validator API with your key. The client wraps the same HTTPS request, so anything it returns is what the endpoint returns.

Install — NuGet

dotnet add package APIVerve.API.SEOValidator

C# / .NET

using var client = new HttpClient();
client.DefaultRequestHeaders.Add("x-api-key", "YOUR_API_KEY");

var json = await client.GetStringAsync("https://api.apiverve.com/v1/seovalidator");
Console.WriteLine(json);

Resources

NuGetAPIVerve.API.SEOValidatorThe published C# / .NET client, versioned and signed.GitHubapiverve/seovalidator-apiSource, issues and the examples this page is built from.ReferenceSEO Quick Validator API docsEvery parameter, every response field, and the errors.ParametersWhat this call acceptsRequired and optional inputs, with example values.

Also published for

@apiverve/seovalidatornpm apiverve-seovalidatorPyPI

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Go — POST /v1/seovalidator

No SDK to install — this is a plain HTTPS call to /v1/seovalidator with your key in the x-api-key header. Swap in a real key and it runs as-is.

req, _ := http.NewRequest("GET", "https://api.apiverve.com/v1/seovalidator", nil)
req.Header.Set("x-api-key", "YOUR_API_KEY")

res, _ := http.DefaultClient.Do(req)
defer res.Body.Close()
body, _ := io.ReadAll(res.Body)
fmt.Println(string(body))

Resources

Also published for

@apiverve/seovalidatornpm apiverve-seovalidatorPyPI APIVerve.API.SEOValidatorNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from PHP — POST /v1/seovalidator

No SDK to install — this is a plain HTTPS call to /v1/seovalidator with your key in the x-api-key header. Swap in a real key and it runs as-is.

PHP

$ch = curl_init("https://api.apiverve.com/v1/seovalidator");
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_HTTPHEADER, ["x-api-key: YOUR_API_KEY"]);

$response = curl_exec($ch);
echo $response;

Resources

Also published for

@apiverve/seovalidatornpm apiverve-seovalidatorPyPI APIVerve.API.SEOValidatorNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

Call it from Ruby — POST /v1/seovalidator

No SDK to install — this is a plain HTTPS call to /v1/seovalidator with your key in the x-api-key header. Swap in a real key and it runs as-is.

Ruby

require "net/http"

uri = URI("https://api.apiverve.com/v1/seovalidator")
req = Net::HTTP::Get.new(uri)
req["x-api-key"] = "YOUR_API_KEY"

res = Net::HTTP.start(uri.hostname, uri.port, use_ssl: true) { |h| h.request(req) }
puts res.body

Resources

Also published for

@apiverve/seovalidatornpm apiverve-seovalidatorPyPI APIVerve.API.SEOValidatorNuGet

Only the languages APIVerve ships a client for are listed — the rest call the endpoint directly over HTTPS.

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SEO Quick Validator API

Try it — live request, no key required

About the SEO Quick Validator API

What people use it for

Ways to call it

Other ways to use SEO Quick Validator

Questions.

Request parameters — POST /v1/seovalidator

Required

Authentication

Response — POST /v1/seovalidator

Response fields

Response headers

Errors

What a call costs — 10 credits per call

Call it from cURL — POST /v1/seovalidator

Resources

Also published for

Call it from Node.js — POST /v1/seovalidator

Resources

Also published for

Call it from Python — POST /v1/seovalidator

Resources

Also published for

Call it from C# / .NET — POST /v1/seovalidator

Resources

Also published for

Call it from Go — POST /v1/seovalidator

Resources

Also published for

Call it from PHP — POST /v1/seovalidator

Resources

Also published for

Call it from Ruby — POST /v1/seovalidator

Resources

Also published for

Zero-code embed — one snippet, no backend

Changelog — SEO Quick Validator API

Data Validation

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