As you probably know already, it’s important to check and test your Website to help ensure that it looks great and works beautifully regardless of the browser or platform used. Testing a website before launch is one thing that you cannot afford to take lightly.  Just like a minor negligence while constructing a building can cost life of millions of residents , the same way a small error left unnoticed can prove to be fatal for your website.

Therefore, this implies that we must run our website through all necessary tests. This includes CSS Errors, HTML Errors, Cross browsing Errors, WAP Errors (if your site is WAP enabled) and various other tests.Below is the list of Online Tools for Website Validation and Testing. So make it sure that you go through this post and run all the necessary tests on your website before making it live.

Website Validation Tools

1.W3C markup validation service

This validator checks the markup validity  of Web documents in HTML, XHTML, SMIL, MathML, etc. This is an exclusive standards check for the document, so other checks are not available.

Checks done on:

  1. Syntax and style analysis – Yes
  2. Source code – Yes

2.CSS validator

Check Cascading Style Sheets (CSS) and (X)HTML documents with style sheets.The important thing is if you want to validate your CSS style sheet embedded in an (X)HTML document, you should first check that the (X)HTML you use is valid.


Check links and anchors in Web pages or full Web sites.This Link Checker looks for issues in links, anchors and referenced objects in a Web page, CSS style sheet, or recursively on a whole Web site. For best results, it is recommended to first ensure that the documents checked use Valid (X)HTML Markup and CSS.


This is the W3C Feed Validation Service, a free service that checks the syntax of Atom or RSS feeds.You can validate by URL or Validate by direct input.

5.Mobile checker

This checker performs various tests on a Web Page to determine its level of mobile-friendliness. The tests are defined in the mobileOK Basic Tests 1.0 specification. A Web Page is mobileOK when it passes all the tests. And find Is your Web site mobile-friendly?

6.HTML Validator

The WDG HTML Validator is similar in many ways to the W3C HTML Validation Service. Most of the previous differences between the two validators have disappeared with recent development of the W3C validator. The errors reported are the same in virtually all cases.

7.Dr. Watson’s site validation check

Dr. Watson is a free service to analyze your web page on the Internet. Just give the URL of your page and Watson will get a copy of it directly from the web server. Watson can also check out many other aspects of your site, including link validity, download speed, search engine compatibility, and link popularity. It rolls many features into one, so if you are looking for a single stop for checks, this one is the place to be.

List of checks :

  1. Page load time check – Yes
  2. Syntax and style analysis – Yes
  3. Word counts – Yes
  4. Spelling checks – Yes
  5. Link checking – Yes
  6. Search Engine Optimization check – Yes
  7. Incoming links check – Yes
  8. Source code – Yes

8.XML well checker and validator

Use this form to check an XML document for well-formetness and (optionally) validity. External entity references are included, even when not validating.It checks for spaces and syntax errors, while pointing to the line number at which the error was spotted.

9.Robots checker

This tool checks if your Robots.txt file is valid. Thought it may show some exclusions you’ve done as errors, they are good pointers to check if the commands will be misinterpreted or not. Good one and it is simple,powerful and accurate one.

10.URL checker

While it’s important to know if your website is running and your host is providing a good service, it’s even more important to be proactive about getting it back online fast so you don’t lose search engine position, miss out on possible revenue or blow.InternetSupervision™ is a service that monitors the availability of HTML, FTP, SMTP, POP3 email servers), supervises the performance of website and e-commerce transactions (including website forms) and provides website content supervision (cyber-attack monitoring).

Accessibility and evaluation tools

11.Webaccessibility checker

This tool checks single HTML pages for conformance with accessibility standards to ensure the content can be accessed by everyone. See the Handbook link to the upper right for more about the Web Accessibility Checker.

12.Color contrast

AccessColor tests the color contrast and color brightness between the foreground and background of all elements in the DOM to make sure that the contrast is high enough for people with visual impairments. AccessColor will find the relevant color combination within your HTML and CSS documents rather than requiring you to find each value to input yourself in order to test the contrast between each color combination.

13.Web accessibily evaluation tool-WAVE

WAVE is a free web accessibility evaluation tool provided by WebAIM. It is used to aid humans in the web accessibility evaluation process. Rather than providing a complex technical report, WAVE shows the original web page with embedded icons and indicators that reveal the accessibility of that page.

14.Accessibility with style

HERA is a tool to check the accessibility of Web pages according to the specification Web Content Accessibility Guidelines. HERA performs a preliminary set of tests on the page and identifies any automatically detectable errors or checkpoints met, and which checkpoints need further manual verification.

15.Adobe PDF conversion

This conversion service will convert to text Adobe PDF files that are in English.By submitting content through these tools, you understand and agree that Adobe may occasionally access the content you submit for purposes of quality control and administration of the conversion service.

Website performance checkers

16.Pingdom tools

The Full Page Test loads a complete HTML page including all objects (images, CSS, JavaScripts, RSS, Flash and frames/iframes). It mimics the way a page is loaded in a web browser.The load time of all objects is shown visually with time bars.

17.Webpage analyzer

Free web site speed test to improve website performance.The script calculates the size of individual elements and sums up each type of web page component. Based on these page characteristics the script then offers advice on how to improve page load time

Cross Browser Testing

18.Browser Shots

Browsershots makes screen shots of your web design in different operating systems and browsers. It is a free open-source online web application providing developers a convenient way to test their website’s browser compatibility in one place. When you submit your web address, it will be added to the job queue. A number of distributed computers will open your website in their browser. Then they will make screenshots and upload them to our central dedicated servers for your review.

19.IE net renderer

IE NetRenderer allows you to check how a website is rendered by Internet Explorer 7, 6 or 5.5, as seen from a high-speed data center located in Germany.


viewlike allows you to check out how your website looks in the most popular resolution formats. It’s all powered by Ajax & PHP so no need to download anything! To Get started just type your URL in the box above. Free to use!

Which tools do you use for your website? Feel free to share them with us via comments.

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