Page Size & Resource Checker
Measure HTML size and count common page resources.
Check Page SizeWebsite Tools
Extract and validate JSON-LD structured data from a public webpage. Clear limitations are shown and sensitive credentials are never sent to the visitor browser.
The public URL, domain, IP address, record type, or audit option requested by the checker.
Choose only the settings that apply to the result you need; leave optional controls unchanged when you are unsure.
Start the task and wait for the interface to return its result or a clear setup message.
Results can vary by location, cache, DNS propagation and temporary server conditions. Confirm important findings with the relevant host or service.
Measure HTML size and count common page resources.
Check Page SizeMeasure time to first byte and total initial response time.
Measure TTFBReview MX, SPF and DMARC setup without sending an email.
Check DeliverabilityCheck whether a root ads.txt file is reachable and review its authorized seller records.
Check Ads.txtFetch a website robots.txt file and review user-agent, allow, disallow and sitemap directives.
Test Robots.txtThe public URL, domain, IP address, record type, or audit option requested by the checker. Start with a representative input and use only the options needed for your intended result.
A point-in-time observation from the public target and the checks available on this page. A clean automated check does not replace testing in the system where the data or code will be used.
Results can vary by location, cache, DNS propagation and temporary server conditions. Confirm important findings with the relevant host or service.
The checker uses the public target you enter to make a diagnostic request. Do not place credentials or private access tokens in a URL.
The page can be used without creating a visitor account. Your browser or device may limit unusually large files or demanding media jobs.
Use Schema Markup Validator when you need a focused result without installing a separate desktop application. Extract and validate JSON-LD structured data from a public webpage. The result changes when the source data or selected options change, so it is easy to run a second comparison.
The public URL, domain, IP address, record type, or audit option requested by the checker.
A point-in-time observation from the public target and the checks available on this page.
It can help when you need to run a fresh diagnostic after a hosting, DNS, certificate, redirect, content or performance change. Start with a representative input, inspect the first result, then adjust one setting at a time if you need a different outcome.
The checker uses the public target you enter to make a diagnostic request. Do not place credentials or private access tokens in a URL.