Free comparer

Compare raw HTML vs rendered HTML

See what the server sends first, what JavaScript adds, and whether crawlers may be missing important page content.

All free tools
Run the check

Check what exists before JavaScript runs

The result highlights how much readable content exists before JavaScript compared with the rendered page.

01Initial raw HTML text length
02Rendered page text length
03Crawler-readable content gap

Bare domains use HTTPS and the www hostname by default.

Tool fit

When to use this tool

01
Thin initial HTML

Your app ships a small root div and JavaScript bundle before real content appears.

02
Browser proof is not enough

You need to show why a finished browser preview does not prove crawler readability.

03
Prerendering fit

Use the gap to decide whether rendered HTML for bots would solve the problem.

What the result means

Does JavaScript contain most of the page?

A large gap means the browser can see useful content that is absent from the first response. Review the missing headings, copy, links, and metadata—not only the text ratio.

It does not promise rankings, traffic, or AI citations. It tells you whether bots are getting useful HTML from the request path.

Watch first

The rendered page contains substantially more useful content than the raw response. Crawlers that do not execute JavaScript reliably may receive an incomplete page.

Good sign

The raw response already contains the page's important content and signals. A separate rendering layer may not be necessary for this URL.

Common warning signs

Very low readable text, generic metadata, missing headings, blocked crawler access, or a large raw-versus-rendered gap.

Next step

If the rendered page has much more content

Confirm the same gap on important routes, then choose SSR, static generation, or crawler rendering. If raw HTML is already complete, leave the delivery path alone.