A dead link checker crawls the website and checks for existing links on it. Each link is checked to ensure that it is still working. Common issues are renamed webpages, redirects on the target website, or dead websites.

The service is offered by different tools:

• W3C Checker: https://validator.w3.org/checklink
  Can be slow in checking all outgoing links
• Dead Link Checker: https://www.deadlinkchecker.com/
• Dr. Link Check: https://www.drlinkcheck.com/
  Free accounts are limited in the number of checked links.

The website can convert between different table formats. It supports CSV, Markdown, SQL, HTML. It is useful when embedding CSV data into Markdown or similar.

The website can convert between different table formats. It supports dozens of formats like Excel, CSV, HTML tables, Markdown, arrays in many languages, or LaTeX.

The website lets you create very customizable tables. It supports splitting and merging cells, customized lines around each cell, and coloring. The website supports LaTeX, HTML, and Markdown output.

The W3C Link Checker crawls your website and reports broken or outdated links. The tool reports on broken links (e.g., 404), broken or missing websites, and links that should be updated to a new location.

Many more W3C checkers exist, for example, HTML, CSS, or RSS validation. https://www.w3.org/developers/tools/ provides an overview.