FXT1 is a texture compression scheme for 3D graphics, invented by the hardware vendor 3dfx Interactive and offered as an open source rival standard to S3TC in September 1999, a year after S3TC had been adopted by Microsoft as part of DirectX. Limited vendor hardware support has been a barrier to its acceptance. Notably, despite being open source, FXT1 was not adopted by Nintendo for the GameCube, nor by Sony for the PlayStation 3, in both cases losing out to the established S3TC standard. Another possible reason for its lack of adoption is that the CC_MIXED mode (see below) probably infringes the S3TC patent ().

Four different compression algorithms are used by FXT1, chosen at a block level to optimize visual quality. who have continued to support S3TC as their preferred compression tool.

Compression algorithms

Four different compression algorithms are set out in the original white paper: