Free HTML Source Viewer

Viewing a page's source is basic SEO reconnaissance — but a web page can't fetch another site's HTML for you (CORS would make that a security nightmare). NToolHub's HTML Source Viewer gives you the legitimate workaround: a drag-to-bookmarks source-viewer bookmarklet plus a view-source: URL opener for Chromium and Firefox.

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Why no live result here? Fetching and displaying another site’s raw HTML inside a web page is blocked by CORS — and rendering it would be a security risk. Instead, this tool builds the exact commands and one-click lookup links you need — everything runs from your own terminal or trusted lookup services.
The workaround: a bookmarklet runs with the privileges of the page you’re already on, so it can open that page’s source directly. Drag it to your bookmarks bar once, then click it on any page.

      

      
Create a new bookmark, paste this as the URL, then click it on any page to view its source.

    

      
      

        
        

    
    

  

  
 Private by design. Nothing is fetched or uploaded — the bookmarklet runs locally on pages you already have open in your own browser.

  

    
How to Use the HTML Source Viewer

    
    
      
  1. Copy the bookmarklet code above.
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  2. Create a new bookmark in your browser and paste the code as its URL.
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  3. Visit any page and click the bookmark — its source opens in a new tab.
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  4. Alternatively, paste a URL below and hit Open view-source:.
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Features

    
Copy-ready bookmarklet code that opens view-source: for whatever page you're on, one-click view-source: opener for any pasted URL, and clear setup instructions — no extensions, no fake fetches.

    
Benefits & Use Cases

    
You inspect real, current page source — including the exact HTML Google sees — with a one-click tool that works on any site, behind logins included, since it runs with your own browsing privileges.

    
Tips

    
Use view-source: to audit meta tags, schema and heading structure; remember it shows initial HTML (not JS-rendered DOM — use DevTools Elements for that); keep the bookmarklet on your bookmarks bar permanently.

  

  

    
Frequently Asked Questions

    
Why can't this tool fetch the HTML for me?
A page fetching and displaying another site's raw HTML would be a cross-site data leak — browsers block it via CORS. The bookmarklet runs with your own page privileges instead, which is both legitimate and more powerful.

    
How do I install the bookmarklet?
Copy the code, create a new bookmark, paste the code as the bookmark's URL. Click it on any page to open that page's source in a new tab.

    
Does view-source work in all browsers?
Chrome, Edge and Firefox support view-source:. Safari doesn't — use Develop → Show Page Source instead.

    
view-source vs DevTools Elements — what's the difference?
view-source: shows the raw HTML the server sent (what crawlers get); DevTools Elements shows the live DOM after JavaScript runs. SEOs need both.

  

  

    
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