Did you know?

Once upon a time, there were over 314,000 articles - some 8.9% of the encyclopedia then - tagged as unreferenced! Thanks to WikiProject Unreferenced articles volunteers searching out and adding references over the years, we are now at about an eighth of that number, about 0.6% of the encyclopedia now.

The MAR26 backlog drive run by WikiProject Unreferenced articles is well under way, with over 120 participants. During these drives, we focus on reducing the number of articles that containing no references, by searching for and adding inline citations to reliable sources that verify claims made in the article.

Over the years, we have made enormous progress in getting sources into articles. Fifteen years ago, there were over 314,000 articles tagged as unsourced. Today, there are only about 39,000 left to go and a shrinking number of articles that have yet to be tagged. The backlog drives are a key part of our success. Please sign up and help us get the total number down to zero.

Our goals for this drive are fourfold:

• Add inline citations to at least 6,000 unreferenced articles
• Bring the total backlog to below 60,000 articles
• Clear the backlog of unreferenced biographies of living persons completely
• Finally clear the Category:Articles lacking sources from December 2009 backlog!

This chart shows how the backlog (that is, the number of articles in Category:All articles lacking sources) has changed over time.^[a] The highest recorded point was an eye-watering 314,663 articles on 15 December 2010. That was partly due to a bot that was run at the end of 2009, which added some 110,838 articles to Category:Articles lacking sources from December 2009.

Thankfully it is been on a decent downward trend since then, and we have been able to make a good dent in the backlog in all our past backlog drives.

• In WP:FEB24, we went from 111,643 tagged unreferenced articles to 97,343, a net decrease of 14,300.
• In WP:NOV24, we went from 80,645 tagged unreferenced articles to 72,134, a net decrease of 8,511. We also (temporarily) reduced the number of unreferenced BLPs to zero.
• In WP:JUN25, we went from c. 58,500 tagged unreferenced articles to 49,028, a net decrease of 9,509 which surpassed our goal of getting under 50,000.
• In WP:NOV25, we went from 47,658 tagged unreferenced articles to 40,259, a net decrease of 7,399. And again, we brought the number of unreferenced BLPs to zero.

There is more historical data that shows the size of the monthly backlog categories over time.

Since the end of September 2025, we have been tracking both tagged unreferenced articles – that is, articles not undergoing a deletion process that are tagged as {{unreferenced}} or a variant – and probably unreferenced articles – that is, those articles that are likely to be unreferenced but are not tagged as such, as determined by ARandomName123's excellent bot, which runs once a day. For more information on the latter set, see this discussion.

The chart below shows that tracking; for context, it equates roughly to the little dashed box on the bottom right of the historical chart above. At the beginning of the day (UTC) on 28 February 2026 there were:

• 39,362 tagged unreferenced articles, a change of −60 since the day before
• 27,855 probably unreferenced articles, a change of −5 since the day before
• That is, a total backlog of 67,217 articles still to deal with, a change of −65 since the day before

At the current average rate of 132 articles per day, it will take 510 days to clear the backlog, finishing on 23 July 2027. (raw data)

Here are a few of the oldest articles that are tagged as unreferenced. Please do cite 'em up, and join the drive if you'd like to help out more!

• Mass media in Laos
• Negligence per se
• Steal (poker)
• PackBits
• Riddarfjärden
• Tile-based game
• Piet Hein Tunnel
• Easter in Latvia
• Turnpike Lane, Haringey
• Muslim brotherhoods of Senegal
• Mainstream hardcore
• Rex Catholicissimus