iview454_x64_setup.exe

IrfanView 64-bit version.

Advantages of IrfanView 64-bit over 32-bit version:

It can load VERY large files/images (image RAM size over 1.3 GB, for special users)
Faster for very large images (25+ Megapixels, loading or image operations)
Runs 'only' on a 64-bit Windows (Vista, Win7, Win8, Win10)
Advantages of IrfanView 32-bit over 64-bit version:

Runs on a 32-bit and 64-bit Windows
Loads all files/images for normal needs (max. RAM size is about 1.3 GB)
Needs less disc space
All PlugIns will work: not all PlugIns are ported (yet) to 64-bit (like OCR) and some 32-bit PlugIns must be still used in the 64-bit version, some with limitations (see the "Plugins32" folder)
Some old 32-bit PlugIns (like RIOT and Adobe 8BF PlugIn) work only in compatilibilty mode in IrfanView-64 (only 32-bit 8BF files/effects can be used)
Command line options for scanning (/scan etc.) work only in 32-bit (because no 64-bit TWAIN drivers)