borg diff¶

borg [common options] diff [options] ARCHIVE1 ARCHIVE2 [PATH...]

positional arguments
	`ARCHIVE1`	ARCHIVE1 name
	`ARCHIVE2`	ARCHIVE2 name
	`PATH`	paths of items inside the archives to compare; patterns are supported.
options
	`--numeric-ids`	only consider numeric user and group identifiers
	`--same-chunker-params`	override the check of chunker parameters
	`--format FORMAT`	specify format for differences between archives (default: “{change} {path}{NL}”)
	`--json-lines`	Format output as JSON Lines.
	`--sort-by`	Sort output by comma-separated fields (e.g., ‘>size_added,path’).
	`--content-only`	Only compare differences in content (exclude metadata differences)
Common options
Include/Exclude options
	`-e PATTERN`, `--exclude PATTERN`	exclude paths matching PATTERN
	`--exclude-from EXCLUDEFILE`	read exclude patterns from EXCLUDEFILE, one per line
	`--pattern PATTERN`	include/exclude paths matching PATTERN
	`--patterns-from PATTERNFILE`	read include/exclude patterns from PATTERNFILE, one per line

Description¶

This command finds differences (file contents, metadata) between ARCHIVE1 and ARCHIVE2.

For more help on include/exclude patterns, see the output of the borg help patterns command.

The FORMAT specifier syntax¶

The --format option uses Python’s format string syntax.

Examples:

$ borg diff --format '{content:30} {path}{NL}' ArchiveFoo ArchiveBar
modified:  +4.1 kB  -1.0 kB    file-diff
...

# {VAR:<NUMBER} - pad to NUMBER columns left-aligned.
# {VAR:>NUMBER} - pad to NUMBER columns right-aligned.
$ borg diff --format '{content:>30} {path}{NL}' ArchiveFoo ArchiveBar
   modified:  +4.1 kB  -1.0 kB file-diff
...

The following keys are always available:

NEWLINE: OS dependent line separator
NL: alias of NEWLINE
NUL: NUL character for creating print0 / xargs -0 like output
SPACE: space character
TAB: tab character
CR: carriage return character
LF: line feed character

Keys available only when showing differences between archives:

path: archived file path
change: all available changes
content: file content change
mode: file mode change
type: file type change
owner: file owner (user/group) change
group: file group change
user: file user change
link: file link change
directory: file directory change
blkdev: file block device change
chrdev: file character device change
fifo: file fifo change
mtime: file modification time change
ctime: file change time change
isomtime: file modification time change (ISO 8601)
isoctime: file creation time change (ISO 8601)

What is compared¶

For each matching item in both archives, Borg reports:

Content changes: total added/removed bytes within files. If chunker parameters are comparable, Borg compares chunk IDs quickly; otherwise, it compares the content.
Metadata changes: user, group, mode, and other metadata shown inline, like “[old_mode -> new_mode]” for mode changes. Use --content-only to suppress metadata changes.
Added/removed items: printed as “added SIZE path” or “removed SIZE path”.

Output formats¶

The default (text) output shows one line per changed path, e.g.:

+135 B    -252 B [ -rw-r--r-- -> -rwxr-xr-x ] path/to/file

JSON Lines output (--json-lines) prints one JSON object per changed path, e.g.:

{"path": "PATH", "changes": [
    {"type": "modified", "added": BYTES, "removed": BYTES},
    {"type": "mode", "old_mode": "-rw-r--r--", "new_mode": "-rwxr-xr-x"},
    {"type": "added", "size": SIZE},
    {"type": "removed", "size": SIZE}
]}

Sorting¶

Use --sort-by FIELDS where FIELDS is a comma-separated list of fields. Sorts are applied stably from last to first in the given list. Prepend “>” for descending, “<” (or no prefix) for ascending, for example --sort-by=">size_added,path". Supported fields include:

path: the item path
size_added: total bytes added for the item content
size_removed: total bytes removed for the item content
size_diff: size_added - size_removed (net content change)
size: size of the item as stored in ARCHIVE2 (0 for removed items)
user, group, uid, gid, ctime, mtime: taken from the item state in ARCHIVE2 when present
ctime_diff, mtime_diff: timestamp difference (ARCHIVE2 - ARCHIVE1)

Performance considerations¶

diff automatically detects whether the archives were created with the same chunker parameters. If so, only chunk IDs are compared, which is very fast.

Examples¶

$ borg diff archive1 archive2
    +17 B      -5 B [-rw-r--r-- -> -rwxr-xr-x] file1
   +135 B    -252 B file2
added           0 B file4
removed         0 B file3

$ borg diff archive1 archive2
{"path": "file1", "changes": [{"type": "modified", "added": 17, "removed": 5}, {"type": "mode", "old_mode": "-rw-r--r--", "new_mode": "-rwxr-xr-x"}]}
{"path": "file2", "changes": [{"type": "modified", "added": 135, "removed": 252}]}
{"path": "file4", "changes": [{"type": "added", "size": 0}]}
{"path": "file3", "changes": [{"type": "removed", "size": 0}]}


# Use --sort-by with a comma-separated list; sorts apply stably from last to first.
# Here: primary by net size change descending, tie-breaker by path ascending
$ borg diff --sort-by=">size_diff,path" archive1 archive2
    +17 B      -5 B [-rw-r--r-- -> -rwxr-xr-x] file1
removed         0 B file3
added           0 B file4
   +135 B    -252 B file2