The mkbrr modify command allows you to update metadata in existing .torrent files without needing access to the original content files. This is useful for mass-updating trackers, source tags, comments, or other metadata.

Arguments

Required command arguments

Flags

Available modification options

Examples

Common usage examples
By default, the original torrent files are preserved. New, modified files are created with a prefix based on the tracker domain (e.g., tracker-domain_original-name.torrent). You can customize the output filename or directory.
The modify command strips all non-standard metadata during the process to ensure clean output.

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Arguments

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torrent files...
string[]
required
One or more paths to the .torrent files you want to modify. Glob patterns (like *.torrent) can be used if your shell supports them.

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Flags

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Input & Output

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--tracker, -t
string
Set a new tracker URL (replaces existing).
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--output-dir
string
Output directory for modified files.
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--output, -o
string
Custom output filename (without extension).
When modifying multiple torrents, using --output with a fixed filename will cause subsequent files to overwrite the previous ones. Use --output-dir instead for batch modifications to preserve all modified files with unique names.

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Advanced Input (Presets)

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--preset, -P
string
Use preset from config.
For reusing common settings across torrents. See the Presets documentation for details.
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--preset-file
string
Preset config file (default ~/.config/mkbrr/presets.yaml).
Set custom path to presets.yaml. See the Presets documentation for details.

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Torrent Internals

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--private, -p
boolean
default:true
Make torrent private.
Private flag is enabled by default for tracker compliance. Only disable if you’re creating a public torrent.
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--entropy, -e
boolean
default:false
Randomize the torrent’s info hash by adding or updating a unique, random entropy key in the info dictionary before hashing.
Cross-seeding is the practice of seeding the same content on multiple trackers. Using the entropy flag helps avoid conflicts between trackers.

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Seeding & Metadata

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--web-seed, -w
array
Specify web seed URLs. Can be used multiple times.
Web seeds provide an HTTP fallback source for the torrent content, improving availability.
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--source, -s
string
Specify the source string.
Some trackers require or recommend specific source tags. Check your tracker’s rules.
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--comment, -c
string
Specify a comment.
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--no-date, -d
boolean
default:false
Omit the creation date from the torrent metadata.
If omitted, the creation date is updated to the current time during modification.
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--no-creator
boolean
default:false
Omit the creator string from the torrent metadata.

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Execution & Output Control

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--verbose, -v
boolean
default:false
Be verbose.
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--quiet
boolean
default:false
Enable quiet mode, printing only the final torrent file path upon success. Useful for scripts.
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--dry-run, -n
boolean
default:false
Show what would be modified without making changes.

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Examples

Update the tracker for a single torrent:
mkbrr modify original.torrent --tracker https://new-tracker.com/announce
Outputs: new-tracker_original.torrent
Make multiple torrents public:
mkbrr modify *.torrent --private=false
Outputs: modified_file1.torrent, modified_file2.torrent, etc.
mkbrr modify [torrent files...] [flags]
By default, the original torrent files are preserved. New, modified files are created with a prefix based on the tracker domain (e.g., tracker-domain_original-name.torrent). You can customize the output filename or directory.
The modify command strips all non-standard metadata during the process to ensure clean output.