git-sizer VS Callzo

• Comprehensive Repository Analysis
  git-sizer analyzes many different dimensions of a Git repository including commit count, tree size, blob size, history depth, and reference counts, providing a holistic view of repository health and potential scaling issues.
• Easy to Use
  The tool is simple to run with minimal setup—just execute it within a git repository—and it produces clear, human-readable output that highlights potential problem areas without requiring complex configuration.
• Identifies Performance Bottlenecks
  It helps identify specific issues that could degrade Git performance, such as excessively large blobs, deep history, large trees, or too many references, which is valuable before migrating or scaling repositories.
• Open Source and Maintained by GitHub
  Being an official GitHub project, it benefits from credibility, community trust, and ongoing maintenance, and it is well documented with clear explanations of what each metric means.
• Useful for Pre-Migration Checks
  It's particularly helpful for teams migrating repositories to new platforms or consolidating repos, as it flags potential issues that could cause problems during migration or with hosting providers' limits.

Possible disadvantages

• No Automatic Remediation
  git-sizer only identifies and reports issues but does not offer any built-in tools or automated processes to fix problems like large blobs or excessive history depth—users must use separate tools like BFG Repo-Cleaner or git-filter-repo.
• Output Can Be Overwhelming for Beginners
  While detailed, the output includes many metrics and threshold levels that may be confusing for users unfamiliar with Git internals, requiring some learning curve to fully interpret results.
• Limited to Local Analysis
  The tool analyzes a local clone of the repository, so it requires users to have a full local copy of the repo (or at least enough history) to get accurate results, which can be time-consuming for very large repositories.
• No Real-Time Monitoring
  It functions as a one-time analysis tool rather than providing continuous or real-time monitoring of repository health, requiring manual reruns to track changes over time.
• Command-Line Only Interface
  The tool lacks a graphical user interface, which may be less accessible for users who prefer visual dashboards or are less comfortable with command-line tools.

No features have been listed yet.

• how to keep github repos small?

  Also there’s a cool project from GitHub you can use to help understand the size of git’s objects in your git repo https://github.com/github/git-sizer. This might help you determine what the best cloning strategy could be. Source: about 5 years ago

Tracking Callzo since Mar 2026.