FCEUX 2.6.6 was available to download from the developer's website when we last checked. We cannot confirm if there is a free download of this software available. The most popular versions among FCEUX users are 2.2 and 2.1. The FCEUX installer is commonly called fceux.exe.
The latest version of the software can be downloaded for PCs running Windows XP/Vista/7/8/10/11, 32-bit. This free software is an intellectual property of FCEUX. The program lies within Games, more precisely Utilities. We recommend checking the downloaded files with any free antivirus.
From the developer:
FCEUX is a Nintendo Entertainment System (NES), Famicom, and Famicom Disk System (FDS) emulator. It supports both PAL (European) and NTSC (USA/JPN) modes. FCEUX offers tools for debugging, rom-hacking, map making, Tool-assisted movies, and Lua scripting.
You may want to check out more software, such as OfflineList, Smart Mod Manager or Redblade, which might be related to FCEUX.