Comparison, updated 4 November 2026
Reading an unfamiliar repository is slow. A generated diagram will not replace reading the code, but it gets you a map in a minute. The tools below read a GitHub repository and draw it; they differ in whether the result is editable, whether private repos work, and what you can do with the diagram afterwards.
We make Archreactor, one of the tools listed. Competitor facts come from each vendor's own page on 4 November 2026. Generated diagrams from any of these tools can be wrong, so check them against the code before you rely on them.
1
Best for a quick look at a public repo
Anyone who wants a quick picture of a public GitHub repository, no account needed.
Pricing. Free to use at the time of writing; see the site.
2
Best for reading docs about a repo, with diagrams
Developers who want to read generated documentation, with diagrams, about an unfamiliar repository.
Pricing. Free for public repositories at the time of writing; see the site.
3
Best for an editable diagram you can present and share
People who need to explain a system: presales, onboarding, design reviews, interview prep.
Pricing. Free; Starter $10/month; Pro $19/month per editor; Team $49/user/month (paid plans are not yet open for purchase).
4
Best if you already work in Eraser
Engineering teams that want diagrams and docs in one workspace, written as code or drawn.
Pricing. Free; Business $45 per member per month billed annually ($60 monthly); Business Plus $42 per member (10 seat minimum); Enterprise custom. Source: eraser.io/pricing.
For a throwaway look at a public repo, GitDiagram is the quickest. To read about a codebase, DeepWiki. To end up with a diagram you can edit, present as a walkthrough and share, use Archreactor (public or private repos; the free plan includes 3 imports a month). If your team already uses Eraser with GitHub, stay there.
It shows structure the model could infer from files. It will miss runtime behaviour, infrastructure defined outside the repo and anything the team never wrote down. Treat it as a first draft, then correct it.
Free, no card. Describe a system or import a repo and see the diagram in about a minute.
We make Archreactor. Competitor details were read from each vendor's own pages on 4 November 2026 and can change; follow the links for current plans. Spot an error? Tell us on the contact page and we will fix it.