This work evaluated the performance characteristics of the Biograph Vision.X PET/CT system according to the NEMA NU 2-2018 standards. This novel system is based on the Biograph Vision 600 with an axial field-of-view of 26.1 cm, consisting of 8 rings of 38 detector blocks using the same detector modules combining 5 × 5 array of 3.2 × 3.2 × 20 mm lutetium-oxyorthosilicate crystals with 16 × 16 mm array of silicon photomultiplier–based photodetectors. The Biograph Vision.X scanner is a newly released time-of-flight whole-body hybrid PET/CT imaging system featuring exclusive proprietary high-performance detector electronic assembly (DEA) technology with optimized digital electronics and digital processing along the entire imaging chain to achieve fast coincidence time resolution PET. In addition, examples of 3D Hoffman phantom and clinical 18F-FDG brain and whole-body studies were compared with scans performed sequentially after the Biograph Vision 600 PET/CT scanner. The Biograph Vision.X had a radial, tangential and axial spatial resolution in terms of full-width at half-maximum of 3.4, 3.5 and 3.5 mm, respectively, at a 1 cm offset from the center of the field-of-view. The sensitivity was 19.2 cps/kBq at the center and 10 cm off-center, while the peak noise-equivalent count-rate (NECR) was 291 kcps at 27.2 kBq/mL. The TOF resolution varied from 178.7 to 182.0 ps as the count rate increased up to the peak NECR. Generally, the image contrast observed on the NEMA image quality phantom ranged from 74.1% to 91.8%. The Biograph Vision.X is a competitive newly introduced device outperforming its predecessor, the Biograph Vision 600, by reaching the fastest TOF performance in the industry, thus achieving 7.5 TOF gain improvement compared to 6.2 on the Vision 600.