Ultimate Packer for eXecutables Copyright (C) 1996 - 2026 UPX 5.3.0 Markus Oberhumer, Laszlo Molnar & John Reiser Oct 28th 2026 Usage: upx [-123456789dlthVL] [-qvfk] [-o file] file.. Commands: -1 compress faster -9 compress better --best compress best (can be slow for big files) -d decompress -l list compressed file -t test compressed file -V display version number --fileinfo show parameters of already-compressed file -h give this help -L display software license Options: -q be quiet -v be verbose -oFILE write output to 'FILE' -f force compression of suspicious files -i info mode --no-color, --mono, --color, --no-progress change look Compression tuning options: --lzma try LZMA [slower but tighter than NRV] --brute try all available compression methods & filters [slow] --ultra-brute try even more compression variants [very slow] Backup options: -k, --backup keep backup files --no-backup no backup files [default] Overlay options: --overlay=copy copy any extra data attached to the file [default] --overlay=strip strip any extra data attached to the file [DANGEROUS] --overlay=skip don't compress a file with an overlay File system options: --force-overwrite force overwrite of output files --link preserve hard links (Unix only) [USE WITH CARE] --no-link do not preserve hard links but rename files [default] --no-mode do not preserve file mode (aka permissions) --no-owner do not preserve file ownership --no-time do not preserve file timestamp Options for djgpp2/coff: --coff produce COFF output [default: EXE] Options for dos/com: --8086 make compressed com work on any 8086 Options for dos/exe: --8086 make compressed exe work on any 8086 --no-reloc put no relocations in to the exe header Options for dos/sys: --8086 make compressed sys work on any 8086 Options for linux/elf: --preserve-build-id copy .gnu.note.build-id to compressed output --catch-sigsegv debug errors in hardware or de-compressor Options for ps1/exe: --8-bit uses 8 bit size compression [default: 32 bit] --8mib-ram 8 megabyte memory limit [default: 2 MiB] --boot-only disables client/host transfer compatibility --no-align don't align to 2048 bytes [enables: --console-run] Options for watcom/le: --le produce LE output [default: EXE] Options for win32/pe, win64/pe & rtm32/pe: --compress-exports=0 do not compress the export section --compress-exports=1 compress the export section [default] --compress-icons=0 do not compress any icons --compress-icons=1 compress all but the first icon --compress-icons=2 compress all but the first icon directory [default] --compress-icons=3 compress all icons --compress-resources=0 do not compress any resources at all --keep-resource=list do not compress resources specified by list --strip-relocs=0 do not strip relocations --strip-relocs=1 strip relocations [default] file.. executables to (de)compress This version supports: amd64-darwin.dylib dylib/amd64 amd64-darwin.macho macho/amd64 amd64-linux.elf linux/amd64 amd64-linux.kernel.vmlinux vmlinux/amd64 amd64-win64.pe win64/pe arm-darwin.macho macho/arm arm-linux.elf linux/arm arm-linux.kernel.vmlinux vmlinux/arm arm-linux.kernel.vmlinuz vmlinuz/arm arm-wince.pe wince/arm arm64-darwin.macho macho/arm64 arm64-linux.elf linux/arm64 arm64-win64.pe win64/arm64 armeb-linux.elf linux/armeb armeb-linux.kernel.vmlinux vmlinux/armeb fat-darwin.macho macho/fat i086-cpm86.cmd cpm86/cmd i086-dos16.com dos/com i086-dos16.exe dos/exe i086-dos16.sys dos/sys i386-bsd.elf.execve bsd.exec/i386 i386-darwin.macho macho/i386 i386-dos32.djgpp2.coff djgpp2/coff i386-dos32.tmt.adam tmt/adam i386-dos32.watcom.le watcom/le i386-freebsd.elf freebsd/i386 i386-linux.elf linux/i386 i386-linux.elf.execve linux.exec/i386 i386-linux.elf.interp linux/elfi386 i386-linux.elf.shell linux.sh/i386 i386-linux.kernel.bvmlinuz bvmlinuz/i386 i386-linux.kernel.vmlinux vmlinux/i386 i386-linux.kernel.vmlinuz vmlinuz/i386 i386-netbsd.elf netbsd/i386 i386-openbsd.elf openbsd/i386 i386-win32.pe win32/pe m68k-atari.tos atari/tos mips-linux.elf linux/mips mipsel-linux.elf linux/mipsel mipsel.r3000-ps1 ps1/exe powerpc-darwin.macho macho/ppc32 powerpc-linux.elf linux/ppc32 powerpc-linux.kernel.vmlinux vmlinux/ppc32 powerpc64-linux.elf linux/ppc64 powerpc64le-linux.elf linux/ppc64le powerpc64le-linux.kernel.vmlinux vmlinux/ppc64le riscv64-linux.elf linux/riscv64 UPX comes with ABSOLUTELY NO WARRANTY; for details visit https://upx.github.io