Introduction Tag syntax Page structure Validation Useful tags Style sheets Tables Useful links

Although you may not have learnt a lot of HTML yet, the sooner you start validating your web pages, the better. If you validate as you go along, you can be sure that what you are learning is correct. If you build up your knowledge and then start validating, you are likely to find that you need to unlearn a lot of stuff!

The W3C provide a free online validation service at The service can validate html pages which are live and visible on the internet, and it can also validate files which you can upload from your computer.

Go to (this link will open up a new window) and click on the Browse button to upload the index.htm file you just made. Click on Validate File and after a short delay, the validation results will be shown. Hopefully, the file will have passed the test, but if not, any errors will be shown along with links to explanations of the errors, and a line-numbered listing of your html file to help you identify the location of the error.

If your file passed the test, try introducing a mistake - for example, you could change a tag to upper case. Save your file and upload it again. The validator should spot the error - and may also generate a list of further errors which are essentially caused by the first error.

Valid XHTML 1.0! Valid CSS!

Note that this course was written in 2003, and things have moved on since then! You might like to check out this site for a more up to date html overview.

© Dial Solutions 2003
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