WikiBlame is an online browser-based tool for searching the revision history of a MediaWiki-based wiki for a text string to identify the author, date and time of a particular change to the page.

WikiBlame is available on each page by selecting View history → Find addition/removal.

• search the revision history of a wiki article for a plain text string
• search based on simple wiki markup such as links, section headings and templates
• linear search or binary search
• option to specify a start date for the search

• Establish when and by whom vandalism, copyright violations or promotional material was added to an article. This allows users to see whether the problematic editor made other undetected changes at the same time.
• Find out who added a quotation without an inline citation. If the editor is still active, the editor can be asked if they remember where the quote was read, so that an inline citation can be added to the article.
  • Similarly, it can be used to find an editor who added a short citation without adding the corresponding long citation to a references section. This is a fairly common mistake which is made when editors copy text from one article to another. If the editor is still active, they can be contacted to ask whence the copy came, or the text found by WikiBlame can be searched for in other Wikipedia articles to see if the long citation is available in another article.
• Fix this type of error:
  Cite error: The named reference Oxford was invoked but never defined (see the help page).
  (that occurs when someone deletes the original reference which is still used by its name somewhere else in an article) by searching for the name of the reference; e.g. "name=Oxford".
• Find the author of an unsigned entry on a talk page so that the editor can be attributed (see WP:TALK "Attributing unsigned comments").

WikiBlame supports Wikipedia and other wikiprojects, including those without a language prefix.

WikiBlame has been translated into a number of European languages including English, German, Spanish, French, Italian, Greek, Polish and Portuguese.

• WikiBlame manual
• Who Wrote That?

This user uses WikiBlame.

You can add the above userbox to your user page by adding to your page's wiki markup text the following template:

((User:Was a bee/WikiBlame))

Wikimedia Commons has media related to Wikipedia tools.

MediaWiki has documentation related to: Who Wrote That?

• WikiBlame site
• GitHub project page
• Alternative searcher on the Wikimedia Cloud Services server (less accurate)