unmerged-branches-weight

CLI that scans a Git repository and shows how much disk space every unmerged remote branch eats after compression

Why

Over‑grown feature branches slow down git clone and waste storage. Knowing the worst offenders lets you delete or squash them first

How it works

1. Collects all commits reachable from every remote branch
2. Adds commits that are reachable only via tags to a virtual branch called $tags
3. Calculates compressed diff size in bytes per commit. Compression factor: text - 20%, binary - ~70% (depends on extension, see code)
4. Sums the numbers per branch and sorts branches by estimated compressed size

Install

# global
npm i -g unmerged-branches-weight

Usage

# one-off run
npx unmerged-branches-weight
# if installed
unmerged-branches-weight
npm run unmerged-branches-weight

Options
  --repo, -r <path>   # path to the Git repository (default = cwd)
  --out, -o <path>    # output directory for the report (default = <repo>/unmerged-branches-size-report)
  --branch, -b <name> # default branch name (master | main) (auto-detect if not provided)
  --no-prompt, -y     # run non‑interactively, use defaults when possible
  --help, -h          # show usage information

Output

<dir>/
  branches_with_commits_and_sizes.json          full stats, biggest first
  branches_with_sizes.json                      branch‑only summary
  commits_with_branches_and_sizes.json          raw per‑commit data

Example entries by report file

branches_with_sizes.json

{
  "branch": "feature/payments‑v2",
  "estCompressedSize": "7.3 MB",
  "textSize": 1834120,
  "binarySize": 19112702
},
{
  "branch": "$tags",
  "estCompressedSize": "6.5 MB",
  "textSize": 694200,
  "binarySize": 9583150
}

branches_with_commits_and_sizes.json

{
  "branch": "origin/feature/forms‑table",
  "estCompressedSizeMB": "12.5 MB",
  "textSize": 10485760,
  "binarySize": 2621440,
  "estCompressedSize": 13107200,
  "commits": [
    {
      "commit": "a1b2c3d4e5f6a7b8c9d0",
      "textSize": 5242880,
      "binarySize": 1310720,
      "estCompressedSize": 6553600
    },
    {
      "commit": "b2c3d4e5f6a7b8c9d0e1",
      "textSize": 5242880,
      "binarySize": 1310720,
      "estCompressedSize": 6553600
    }
  ]
},
{
  "branch": "origin/hotfix/task‑filter",
  "estCompressedSizeMB": "8.4 MB",
  "textSize": 8388608,
  "binarySize": 0,
  "estCompressedSize": 8388608,
  "commits": [
    {
      "commit": "c3d4e5f6a7b8c9d0e1f2",
      "textSize": 4194304,
      "binarySize": 0,
      "estCompressedSize": 4194304
    },
    {
      "commit": "d4e5f6a7b8c9d0e1f2g3",
      "textSize": 4194304,
      "binarySize": 0,
      "estCompressedSize": 4194304
    }
  ]
}

commits_with_branches_and_sizes.json

{
  "commit": "d4e5f6a7b8c9d0e1f2g3",
  "estCompressedSize": 86376400,
  "estCompressedSizeMB": "82.4 MB",
  "textSize": 16760,
  "binarySize": 172752800,
  "branches": ["origin/feature/billing‑update"]
},
{
  "commit": "e5f6a7b8c9d0e1f2g3h4",
  "estCompressedSize": 71963773,
  "estCompressedSizeMB": "68.6 MB",
  "textSize": 54000,
  "binarySize": 102793173
  // commit reachable only via tags, will be placed in "$tags" branch
},
{
  "commit": "f6a7b8c9d0e1f2g3h4i5",
  "estCompressedSize": 14438189,
  "estCompressedSizeMB": "13.8 MB",
  "textSize": 3160,
  "binarySize": 14438013,
  "branches": [
    "origin/feature/billing‑update",
    "origin/bugs/fix-ai-chat-planning-revolution"
  ]
},

Performance

On ~5k commit repo with 250 remotes and 3k unmerged commits the scan finishes in 3-4 min on an SSD

On ~200k commit repo with 4k remotes and 22k unmerged commits the scan finishes in 15-20 min on an SSD

Limits

• Tested on Node 18+.
• Windows works via Git‑for‑Windows, macOS/Linux work out of the box
• Size is an estimate; for byte‑exact numbers use git verify-pack

License

MIT — PRs and issues welcome