Info command (i)

7z i [format]

# Display all supported formats
7z i

# Show information about 7z format
7z i 7z

# Show information about ZIP format
7z i zip

# Show information about TAR format
7z i tar

$ 7z i

7-Zip 26.00 (x64) : Copyright (c) 1999-2026 Igor Pavlov : 2026-03-01

Formats:
 Lib  ID  Name

   0  01  7z
   0  02  Arj
   0  03  BZip2
   0  04  Cab
   0  05  Chm
   0  06  Compound
   0  07  Cpio
   0  08  CramFS
   0  09  Dmg
   0  0A  ELF
   0  0B  Ext
   0  0C  FAT
   0  0D  FLV
   0  0E  GZip
   0  0F  HFS
   0  10  IHex
   0  11  Iso
   0  12  Lzh
   0  13  Lzma
   0  14  Lzma86
   0  15  MachO
   0  16  Mbr
   0  17  Msi
   0  18  Mub
   0  19  Nsis
   0  1A  Ntfs
   0  1B  PE
   0  1C  Rar
   0  1D  Rar5
   0  1E  Rpm
   0  1F  Split
   0  20  SquashFS
   0  21  SWF
   0  22  SWFc
   0  23  Tar
   0  24  TE
   0  25  Udf
   0  26  UEFIc
   0  27  UEFIs
   0  28  Vhd
   0  29  Wim
   0  2A  Xar
   0  2B  XZ
   0  2C  Z
   0  2D  Zip

Codecs:
 Lib  ID  Name

   0  030101  LZMA
   0  030401  PPMD
   0  040202  BZip2
   0  21      LZMA2

Hashers:
 Lib  Size    ID    Name

   0    4       1   CRC32
   0    8       4   CRC64
   0   32      A    SHA256
   0   20     201   SHA1
   0    8     202   XXH64

# Check if a format is supported
7z i | grep -i "wim"

# Check available codecs
7z i | grep -A 10 "Codecs:"

# Show all hash functions
7z i | grep -A 10 "Hashers:"

# 7z format capabilities
7z i 7z

# Output shows:
# - Supported compression methods
# - Encryption support
# - Solid archive support
# - Multi-volume support

#!/bin/bash

# Check if 7-Zip supports a specific format
check_format() {
    local format=$1
    if 7z i | grep -qi "$format"; then
        echo "Format $format is supported"
        return 0
    else
        echo "Format $format is NOT supported"
        return 1
    fi
}

# Usage
check_format "zip"
check_format "rar"
check_format "7z"

7z i | head -3
# 7-Zip 26.00 (x64) : Copyright (c) 1999-2026 Igor Pavlov : 2026-03-01