IntegerScaler — upscales games with no blur

IntegerScaler is a free author’s program for Windows 7+ intended for pseudo-full-screen upscaling of games in windowed mode with an integer ratio and with no blur.

Allows to play games e. g. at Full-HD (1920×1080) resolution on 4K (3840×2160) monitors with no quality loss, unlike bilinear interpolation used for full-screen scaling by monitors and graphics drivers regardless of whether scaling ratio is integer or not.