For those of us running Apache, htaccess rewrite rules provide an excellent way to block spammers, scrapers, and other scumbags easily and effectively. While there are many htaccess tricks involving blocking domains, preventing access, and redirecting traffic, Apache’s mod_rewrite module enables us to target bad agents by testing the user-agent string against a predefined blacklist of unwanted visitors. Any matches are immediately and quietly denied access.

There are many ways to obtain an effective htaccess blacklist. There are several excellent forums around the web that provide a plethora of priceless htaccess advice. Highly suggested. Additionally, after copying and pasting your favorite forum blacklist examples to your domain’s root htaccess file, you will want to continue with its development by tracking bandwidth thieves, comment spammers, and site scrapers and adding them to the list. Or, you may wish to skip the tedious grunt work and simply grab a copy of the Ultimate htaccess Blacklist!

The Ultimate htaccess Blacklist began as a short list of only the most heinous offenders. Blocking scum was such an enjoyable activity that we soon added to the list the identity of every nasty agent we could find. The result has been a very low-stress, spam-free site with virtually zero stolen bandwidth. The list is fairly comprehensive and attempts to blacklist as many site rippers, grabbers, spammers and bad bots as possible. While no blacklist could ever block them all (nor would they want to using this method)¹, an elaborate htaccess blacklist can do wonders to improve overall performance, decrease site maintenance, and reduce server expense. Overall, we consider this blacklist a great foundation on which to build and customize your own ultimate htaccess blacklist!²

So without further ado, here is our version of the ultimate htaccess blacklist, as promised. Simply copy and paste the following code into the root htaccess file of your site to enjoy a serious reduction in wasted bandwidth, stolen resources, and comment spam. Don’t forget to backup your data and test everything, etc. — After that, you’re good to go!

The Ultimate htaccess Blacklist

# Ultimate htaccess Blacklist from Perishable Press
# Deny domain access to spammers and other scumbags
RewriteEngine on
RewriteBase /
RewriteCond %{HTTP_USER_AGENT} almaden [OR]
RewriteCond %{HTTP_USER_AGENT} ^Anarchie [OR]
RewriteCond %{HTTP_USER_AGENT} ^ASPSeek [OR]
RewriteCond %{HTTP_USER_AGENT} ^attach [OR]
RewriteCond %{HTTP_USER_AGENT} ^autoemailspider [OR]
RewriteCond %{HTTP_USER_AGENT} ^BackWeb [OR]
RewriteCond %{HTTP_USER_AGENT} ^Bandit [OR]
RewriteCond %{HTTP_USER_AGENT} ^BatchFTP [OR]
RewriteCond %{HTTP_USER_AGENT} ^BlackWidow [OR]
RewriteCond %{HTTP_USER_AGENT} ^Bot\ mailto:craftbot@yahoo.com [OR]
RewriteCond %{HTTP_USER_AGENT} ^Buddy [OR]
RewriteCond %{HTTP_USER_AGENT} ^bumblebee [OR]
RewriteCond %{HTTP_USER_AGENT} ^CherryPicker [OR]
RewriteCond %{HTTP_USER_AGENT} ^ChinaClaw [OR]
RewriteCond %{HTTP_USER_AGENT} ^CICC [OR]
RewriteCond %{HTTP_USER_AGENT} ^Collector [OR]
RewriteCond %{HTTP_USER_AGENT} ^Copier [OR]
RewriteCond %{HTTP_USER_AGENT} ^Crescent [OR]
RewriteCond %{HTTP_USER_AGENT} ^Custo [OR]
RewriteCond %{HTTP_USER_AGENT} ^DA [OR]
RewriteCond %{HTTP_USER_AGENT} ^DIIbot [OR]
RewriteCond %{HTTP_USER_AGENT} ^DISCo [OR]
RewriteCond %{HTTP_USER_AGENT} ^DISCo\ Pump [OR]
RewriteCond %{HTTP_USER_AGENT} ^Download\ Demon [OR]
RewriteCond %{HTTP_USER_AGENT} ^Download\ Wonder [OR]
RewriteCond %{HTTP_USER_AGENT} ^Downloader [OR]
RewriteCond %{HTTP_USER_AGENT} ^Drip [OR]
RewriteCond %{HTTP_USER_AGENT} ^DSurf15a [OR]
RewriteCond %{HTTP_USER_AGENT} ^eCatch [OR]
RewriteCond %{HTTP_USER_AGENT} ^EasyDL/2.99 [OR]
RewriteCond %{HTTP_USER_AGENT} ^EirGrabber [OR]
RewriteCond %{HTTP_USER_AGENT} email [NC,OR]
RewriteCond %{HTTP_USER_AGENT} ^EmailCollector [OR]
RewriteCond %{HTTP_USER_AGENT} ^EmailSiphon [OR]
RewriteCond %{HTTP_USER_AGENT} ^EmailWolf [OR]
RewriteCond %{HTTP_USER_AGENT} ^Express\ WebPictures [OR]
RewriteCond %{HTTP_USER_AGENT} ^ExtractorPro [OR]
RewriteCond %{HTTP_USER_AGENT} ^EyeNetIE [OR]
RewriteCond %{HTTP_USER_AGENT} ^FileHound [OR]
RewriteCond %{HTTP_USER_AGENT} ^FlashGet [OR]
RewriteCond %{HTTP_USER_AGENT} FrontPage [NC,OR]
RewriteCond %{HTTP_USER_AGENT} ^GetRight [OR]
RewriteCond %{HTTP_USER_AGENT} ^GetSmart [OR]
RewriteCond %{HTTP_USER_AGENT} ^GetWeb! [OR]
RewriteCond %{HTTP_USER_AGENT} ^gigabaz [OR]
RewriteCond %{HTTP_USER_AGENT} ^Go\!Zilla [OR]
RewriteCond %{HTTP_USER_AGENT} ^Go!Zilla [OR]
RewriteCond %{HTTP_USER_AGENT} ^Go-Ahead-Got-It [OR]
RewriteCond %{HTTP_USER_AGENT} ^gotit [OR]
RewriteCond %{HTTP_USER_AGENT} ^Grabber [OR]
RewriteCond %{HTTP_USER_AGENT} ^GrabNet [OR]
RewriteCond %{HTTP_USER_AGENT} ^Grafula [OR]
RewriteCond %{HTTP_USER_AGENT} ^grub-client [OR]
RewriteCond %{HTTP_USER_AGENT} ^HMView [OR]
RewriteCond %{HTTP_USER_AGENT} ^HTTrack [OR]
RewriteCond %{HTTP_USER_AGENT} ^httpdown [OR]
RewriteCond %{HTTP_USER_AGENT} .*httrack.* [NC,OR]
RewriteCond %{HTTP_USER_AGENT} ^ia_archiver [OR]
RewriteCond %{HTTP_USER_AGENT} ^Image\ Stripper [OR]
RewriteCond %{HTTP_USER_AGENT} ^Image\ Sucker [OR]
RewriteCond %{HTTP_USER_AGENT} ^Indy*Library [OR]
RewriteCond %{HTTP_USER_AGENT} Indy\ Library [NC,OR]
RewriteCond %{HTTP_USER_AGENT} ^InterGET [OR]
RewriteCond %{HTTP_USER_AGENT} ^InternetLinkagent [OR]
RewriteCond %{HTTP_USER_AGENT} ^Internet\ Ninja [OR]
RewriteCond %{HTTP_USER_AGENT} ^InternetSeer.com [OR]
RewriteCond %{HTTP_USER_AGENT} ^Iria [OR]
RewriteCond %{HTTP_USER_AGENT} ^JBH*agent [OR]
RewriteCond %{HTTP_USER_AGENT} ^JetCar [OR]
RewriteCond %{HTTP_USER_AGENT} ^JOC\ Web\ Spider [OR]
RewriteCond %{HTTP_USER_AGENT} ^JustView [OR]
RewriteCond %{HTTP_USER_AGENT} ^larbin [OR]
RewriteCond %{HTTP_USER_AGENT} ^LeechFTP [OR]
RewriteCond %{HTTP_USER_AGENT} ^LexiBot [OR]
RewriteCond %{HTTP_USER_AGENT} ^lftp [OR]
RewriteCond %{HTTP_USER_AGENT} ^Link*Sleuth [OR]
RewriteCond %{HTTP_USER_AGENT} ^likse [OR]
RewriteCond %{HTTP_USER_AGENT} ^Link [OR]
RewriteCond %{HTTP_USER_AGENT} ^LinkWalker [OR]
RewriteCond %{HTTP_USER_AGENT} ^Mag-Net [OR]
RewriteCond %{HTTP_USER_AGENT} ^Magnet [OR]
RewriteCond %{HTTP_USER_AGENT} ^Mass\ Downloader [OR]
RewriteCond %{HTTP_USER_AGENT} ^Memo [OR]
RewriteCond %{HTTP_USER_AGENT} ^Microsoft.URL [OR]
RewriteCond %{HTTP_USER_AGENT} ^MIDown\ tool [OR]
RewriteCond %{HTTP_USER_AGENT} ^Mirror [OR]
RewriteCond %{HTTP_USER_AGENT} ^Mister\ PiX [OR]
RewriteCond %{HTTP_USER_AGENT} ^Mozilla.*Indy [OR]
RewriteCond %{HTTP_USER_AGENT} ^Mozilla.*NEWT [OR]
RewriteCond %{HTTP_USER_AGENT} ^Mozilla*MSIECrawler [OR]
RewriteCond %{HTTP_USER_AGENT} ^MS\ FrontPage* [OR]
RewriteCond %{HTTP_USER_AGENT} ^MSFrontPage [OR]
RewriteCond %{HTTP_USER_AGENT} ^MSIECrawler [OR]
RewriteCond %{HTTP_USER_AGENT} ^MSProxy [OR]
RewriteCond %{HTTP_USER_AGENT} ^Navroad [OR]
RewriteCond %{HTTP_USER_AGENT} ^NearSite [OR]
RewriteCond %{HTTP_USER_AGENT} ^NetAnts [OR]
RewriteCond %{HTTP_USER_AGENT} ^NetMechanic [OR]
RewriteCond %{HTTP_USER_AGENT} ^NetSpider [OR]
RewriteCond %{HTTP_USER_AGENT} ^Net\ Vampire [OR]
RewriteCond %{HTTP_USER_AGENT} ^NetZIP [OR]
RewriteCond %{HTTP_USER_AGENT} ^NICErsPRO [OR]
RewriteCond %{HTTP_USER_AGENT} ^Ninja [OR]
RewriteCond %{HTTP_USER_AGENT} ^Octopus [OR]
RewriteCond %{HTTP_USER_AGENT} ^Offline\ Explorer [OR]
RewriteCond %{HTTP_USER_AGENT} ^Offline\ Navigator [OR]
RewriteCond %{HTTP_USER_AGENT} ^Openfind [OR]
RewriteCond %{HTTP_USER_AGENT} ^PageGrabber [OR]
RewriteCond %{HTTP_USER_AGENT} ^Papa\ Foto [OR]
RewriteCond %{HTTP_USER_AGENT} ^pavuk [OR]
RewriteCond %{HTTP_USER_AGENT} ^pcBrowser [OR]
RewriteCond %{HTTP_USER_AGENT} ^Ping [OR]
RewriteCond %{HTTP_USER_AGENT} ^PingALink [OR]
RewriteCond %{HTTP_USER_AGENT} ^Pockey [OR]
RewriteCond %{HTTP_USER_AGENT} ^psbot [OR]
RewriteCond %{HTTP_USER_AGENT} ^Pump [OR]
RewriteCond %{HTTP_USER_AGENT} ^QRVA [OR]
RewriteCond %{HTTP_USER_AGENT} ^RealDownload [OR]
RewriteCond %{HTTP_USER_AGENT} ^Reaper [OR]
RewriteCond %{HTTP_USER_AGENT} ^Recorder [OR]
RewriteCond %{HTTP_USER_AGENT} ^ReGet [OR]
RewriteCond %{HTTP_USER_AGENT} ^Scooter [OR]
RewriteCond %{HTTP_USER_AGENT} ^Seeker [OR]
RewriteCond %{HTTP_USER_AGENT} ^Siphon [OR]
RewriteCond %{HTTP_USER_AGENT} ^sitecheck.internetseer.com [OR]
RewriteCond %{HTTP_USER_AGENT} ^SiteSnagger [OR]
RewriteCond %{HTTP_USER_AGENT} ^SlySearch [OR]
RewriteCond %{HTTP_USER_AGENT} ^SmartDownload [OR]
RewriteCond %{HTTP_USER_AGENT} ^Snake [OR]
RewriteCond %{HTTP_USER_AGENT} ^SpaceBison [OR]
RewriteCond %{HTTP_USER_AGENT} ^sproose [OR]
RewriteCond %{HTTP_USER_AGENT} ^Stripper [OR]
RewriteCond %{HTTP_USER_AGENT} ^Sucker [OR]
RewriteCond %{HTTP_USER_AGENT} ^SuperBot [OR]
RewriteCond %{HTTP_USER_AGENT} ^SuperHTTP [OR]
RewriteCond %{HTTP_USER_AGENT} ^Surfbot [OR]
RewriteCond %{HTTP_USER_AGENT} ^Szukacz [OR]
RewriteCond %{HTTP_USER_AGENT} ^tAkeOut [OR]
RewriteCond %{HTTP_USER_AGENT} ^Teleport\ Pro [OR]
RewriteCond %{HTTP_USER_AGENT} ^URLSpiderPro [OR]
RewriteCond %{HTTP_USER_AGENT} ^Vacuum [OR]
RewriteCond %{HTTP_USER_AGENT} ^VoidEYE [OR]
RewriteCond %{HTTP_USER_AGENT} ^Web\ Image\ Collector [OR]
RewriteCond %{HTTP_USER_AGENT} ^Web\ Sucker [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebAuto [OR]
RewriteCond %{HTTP_USER_AGENT} ^[Ww]eb[Bb]andit [OR]
RewriteCond %{HTTP_USER_AGENT} ^webcollage [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebCopier [OR]
RewriteCond %{HTTP_USER_AGENT} ^Web\ Downloader [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebEMailExtrac.* [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebFetch [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebGo\ IS [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebHook [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebLeacher [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebMiner [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebMirror [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebReaper [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebSauger [OR]
RewriteCond %{HTTP_USER_AGENT} ^Website [OR]
RewriteCond %{HTTP_USER_AGENT} ^Website\ eXtractor [OR]
RewriteCond %{HTTP_USER_AGENT} ^Website\ Quester [OR]
RewriteCond %{HTTP_USER_AGENT} ^Webster [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebStripper [OR]
RewriteCond %{HTTP_USER_AGENT} WebWhacker [OR]
RewriteCond %{HTTP_USER_AGENT} ^WebZIP [OR]
RewriteCond %{HTTP_USER_AGENT} ^Wget [OR]
RewriteCond %{HTTP_USER_AGENT} ^Whacker [OR]
RewriteCond %{HTTP_USER_AGENT} ^Widow [OR]
RewriteCond %{HTTP_USER_AGENT} ^WWWOFFLE [OR]
RewriteCond %{HTTP_USER_AGENT} ^x-Tractor [OR]
RewriteCond %{HTTP_USER_AGENT} ^Xaldon\ WebSpider [OR]
RewriteCond %{HTTP_USER_AGENT} ^Xenu [OR]
RewriteCond %{HTTP_USER_AGENT} ^Zeus.*Webster [OR]
RewriteCond %{HTTP_USER_AGENT} ^Zeus
RewriteRule ^.* - [F,L]

Footnotes

• ¹ Note: although this blacklist is highly effective at eliminating unwanted scum, its immense length requires extra processing and may affect the performance of your server. In our experience, employing this list (along with several other htaccess directives) for over two years has resulted in zero noticeable performance issues. Nonetheless, this may not be an ideal solution for sites with extreme levels of visitor traffic. [ ^ ]
• ² To begin building your own customized blacklist, you may want to check out the excellent list offered at joemaller.com. Thanks, Joe! [ ^ ]
• ³ Update (October 14,2007): To reduce confusion and consolidate htaccess rules, the last two lines have been removed from the blacklist. These two lines are not required for the blacklist to work as intended:
  RewriteCond %{HTTP_REFERER} ^www.iaea.org$
RewriteRule !^[^/.]\.perishablepress.com.* - [F,L]