Compress files with ZIP, RAR, or 7z
Use efficient file formats
Reduce image resolution
Lower image quality slightly
Remove unnecessary metadata
Resize large images
Convert audio to smaller bitrates
Convert video to more efficient codecs
Trim unused content
Delete duplicate files
Remove embedded fonts and assets
Optimize PDFs
Minify code files
Remove comments and whitespace
Use vector graphics instead of raster images
Split large files if needed
Archive only necessary files
Convert to grayscale when color is not needed
Reduce sample rate for audio
Use lossless compression where possible
Avoid storing unneeded backups inside the file