3dfx Interactive was an American computer hardware company headquartered in San Jose, California, founded in 1994, that specialized in the manufacturing of 3D graphics processing units, and later, video cards. It was a pioneer in the field from the late 1990s until 2000.

The company's original product was the Voodoo Graphics, an add-in card that implemented hardware acceleration of 3D graphics. The hardware accelerated only 3D rendering, relying on the PC's current video card for 2D support. Despite this limitation, the Voodoo Graphics product and its follow-up, Voodoo2, were popular. It became standard for 3D games to offer support for the company's Glide API.

The success of the company's products led to renewed interest in 3D gaming, and by the second half of the 1990s, products combining a 2D output with reasonable 3D performance were appearing. This was accelerated by the introduction of Microsoft's Direct3D, which provided a single high-performance API that could be implemented on these cards, seriously eroding the value of Glide. While 3dfx continued to offer high-performance options, the value proposition was no longer compelling.

3dfx rapidly declined in the late 1990s and most of the company's assets were acquired by Nvidia Corporation on December 15, 2000, mostly for intellectual property rights. The acquisition was accounted for as a purchase by Nvidia and was completed by the first quarter of their fiscal year of 2002. 3dfx ceased supporting their products on February 15, 2001, and filed for bankruptcy on October 15, 2002.