NetCaptor was an Internet Explorer shell that was in development from 1997 to 2005. It used the Trident layout engine of Internet Explorer in conjunction with additional programmed features to create an alternate browsing experience with a tab-based interface and an expanded feature set. It was an adware/shareware program, but its developer released a registration key for free public use once development ceased.

The main features are, as of the last released version, 7.5.4:

After development stopped, one of NetCaptor's most valued features—a side bar and panel that listed search results—also ceased to function. Most other features continue to work. It later releases were not Trident-based Internet Explorer Shells but resembled Internet Explorer 6 in many ways, except for the tabbed browsing feature. Many people^[who?] ceased to use "bare" Internet Explorer in favor of NetCaptor because Internet Explorer 6 lacked tabbed browsing.^{[citation needed]}

NetCaptor's development began under the name SimulBrowse in 1997. SimulBrowse was renamed Netcaptor because the developer didn't like the name. Some of the browser's features were original, while others were inspired by similar products. According to a statement from developer Adam Stiles, NetCaptor was one of the first browsers to feature a tabbed browsing interface; while similarities were found in other browsers of the era (such as Booklink's Internetworks or Opera), NetCaptor's tabs were closest in form and function to the tabs found in modern browsers.