# Black vs Checkstyle

**Leader by vioscaleAI score:** Black

| Attribute | Black | Checkstyle |
|---|---|---|
| **vioscaleAI score** | 73.9 (77% (high)) | 60.1 (49% (low)) |
| activity.commits_last_30d | 75 | 100 |
| adoption.dependent_repos | 105,588 | 1,425 |
| adoption.github_stars | 41,918 | 9,599 |
| adoption.package_downloads_weekly | 27,633,532 | - |
| content.faq | `[{"answer":"An opinionated Python code formatter that automatically reformats code according to a standardized style. It produces minimal diffs for cleaner code review and reduces developer cognitive load by removing formatting decisions, allowing focus on code logic. It is indexed under Code Quality Tools.","source":"https://black.readthedocs.io/en/stable/","question":"What is Black?","confidence":0.6},{"answer":"Black is open source, so it can be self-hosted and used at no licence cost. It is released under the MIT licence. Pricing changes often, so verify at source before relying on it.","source":"https://black.readthedocs.io/en/stable/","question":"Is Black free to use?","confidence":0.6},{"answer":"Black supports a command-line interface. Platforms we have not confirmed are simply not listed here rather than ruled out.","source":"https://black.readthedocs.io/en/stable/","question":"What platforms does Black support?","confidence":0.6},{"answer":"Yes. Black can be deployed self-hosted, so it does not have to run on the vendor's infrastructure.","source":"https://black.readthedocs.io/en/stable/","question":"Can Black be self-hosted?","confidence":0.6},{"answer":"We have confirmed 8 integrations for Black, including Neovim, conform.nvim, ALE, SublimeText, Pre-commit, Jupyter Notebooks, blacken-docs and blackdoc. This is what we could verify from public sources, so the vendor may support others we have not indexed.","source":"https://black.readthedocs.io/en/stable/","question":"What does Black integrate with?","confidence":0.6},{"answer":"Yes. Black is published under the MIT licence, a permissive licence that generally allows commercial use and modification. Licence terms can change between releases, so verify against the repository for the version you intend to use.","source":"https://github.com/psf/black","question":"Is Black open source?","confidence":0.95}]` | `[{"answer":"A development tool that automatically scans Java code to verify adherence to coding standards, detecting style violations, design problems, and formatting issues. Supports customizable rule sets and integrates with build tools and IDEs. It is indexed under Code Quality Tools.","source":"https://checkstyle.org/","question":"What is Checkstyle?","confidence":0.6},{"answer":"Checkstyle supports a command-line interface. Platforms we have not confirmed are simply not listed here rather than ruled out.","source":"https://checkstyle.org/","question":"What platforms does Checkstyle support?","confidence":0.6},{"answer":"Yes. Checkstyle can be deployed self-hosted, so it does not have to run on the vendor's infrastructure.","source":"https://checkstyle.org/","question":"Can Checkstyle be self-hosted?","confidence":0.6},{"answer":"Yes. Checkstyle is published under the LGPL-2.1 licence, a copyleft licence, so check its terms before embedding it in a closed-source product. Licence terms can change between releases, so verify against the repository for the version you intend to use.","source":"https://github.com/checkstyle/checkstyle","question":"Is Checkstyle open source?","confidence":0.95}]` |
| deployment.options | `{"self_hosted":true}` | `{"self_hosted":true}` |
| description.long | A Python code formatter that automatically reformats entire files to enforce consistent styling. It produces minimal diffs to accelerate code review and ensures uniform appearance across projects. | Checkstyle analyzes Java source code against configurable rules covering naming, imports, formatting, Javadoc, and class design. It enables teams to maintain consistent coding standards through CLI, IDE plugins, and CI/CD integrations. |
| features.capabilities | `{"autofix":true,"metrics":false,"function":"formatter","ci_gating":true,"deployment":"both","incremental":false,"open_source":"oss","config_model":"zero_config","custom_rules":false,"impl_language":"Python","pricing_model":"free","language_scope":"single_language","editor_integration":true}` | `{"autofix":false,"metrics":true,"function":"static_analyzer","ci_gating":true,"deployment":"cli_local","open_source":"oss","config_model":"config_file","custom_rules":true,"impl_language":"Java","pricing_model":"free","language_scope":"single_language","editor_integration":true}` |
| integrations.count | 5 | 7 |
| integrations.list | `[{"name":"Neovim"},{"name":"conform.nvim"},{"name":"ALE"},{"name":"SublimeText"},{"name":"Pre-commit"},{"name":"Jupyter Notebooks"},{"name":"blacken-docs"},{"name":"blackdoc"},{"name":"Vim","native":true},{"name":"Visual Studio Code","native":true,"category":"editor","direction":"bidirectional"},{"name":"GitHub Actions","native":true,"category":"ci","direction":"inbound"}]` | `[{"name":"Maven"},{"name":"Ant"},{"name":"Eclipse","native":true,"category":"ide"},{"name":"IntelliJ IDEA","native":true,"category":"ide"},{"name":"Neovim","native":true,"category":"editor"},{"name":"Code Climate","native":true,"category":"code_quality"},{"name":"GitHub Actions","native":true,"category":"ci"},{"name":"Apache Ant","native":true,"category":"build_tool"}]` |
| language.primary | Python | Java |
| license.spdx | MIT | LGPL-2.1 |
| platform.support | `{"cli":true,"linux":true,"windows":true}` | `{"cli":true}` |
| pricing | `{"type":"free","summary":"Free and open source","freeTier":true,"sourceUrl":"https://black.readthedocs.io/en/stable/","retrievedAt":"2026-09-14T09:28:09.046Z"}` | `{"type":"open_source","sourceUrl":"https://checkstyle.org/","retrievedAt":"2026-10-14T22:30:54.455Z"}` |
| pricing.free_tier | yes | yes |
| pricing.model | free | open_source |
| pricing.price_level | free | free |
| pricing.transparent | yes | yes |
| release.cadence_days | 31 | 13 |
| release.history | `[{"url":"https://github.com/psf/black/releases/tag/26.10.1","date":"2026-10-10T04:11:33Z","type":"stable","version":"26.10.1"},{"url":"https://github.com/psf/black/releases/tag/26.10.0","date":"2026-10-04T16:50:23Z","type":"stable","version":"26.10.0"},{"url":"https://github.com/psf/black/releases/tag/26.5.1","date":"2026-05-18T16:52:38Z","type":"stable","version":"26.5.1"},{"url":"https://github.com/psf/black/releases/tag/26.5.0","date":"2026-05-16T17:56:23Z","type":"stable","version":"26.5.0"},{"url":"https://github.com/psf/black/releases/tag/26.3.1","date":"2026-03-12T03:35:15Z","type":"stable","version":"26.3.1"},{"url":"https://github.com/psf/black/releases/tag/26.3.0","date":"2026-03-06T17:41:48Z","type":"stable","version":"26.3.0"},{"url":"https://github.com/psf/black/releases/tag/26.1.0","date":"2026-01-18T04:49:25Z","type":"stable","version":"26.1.0"},{"url":"https://github.com/psf/black/releases/tag/26.1a1","date":"2025-12-08T01:46:21Z","type":"prerelease","version":"26.1a1"},{"url":"https://github.com/psf/black/releases/tag/25.12.0","date":"2025-12-08T01:40:32Z","type":"stable","version":"25.12.0"},{"url":"https://github.com/psf/black/releases/tag/25.11.0","date":"2025-11-10T01:53:31Z","type":"stable","version":"25.11.0"},{"url":"https://github.com/psf/black/releases/tag/25.9.0","date":"2025-09-19T00:27:15Z","type":"stable","version":"25.9.0"},{"url":"https://github.com/psf/black/releases/tag/25.1.0","date":"2025-01-29T04:15:11Z","type":"stable","version":"25.1.0"},{"url":"https://github.com/psf/black/releases/tag/24.10.0","date":"2024-10-07T19:20:06Z","type":"stable","version":"24.10.0"},{"url":"https://github.com/psf/black/releases/tag/24.8.0","date":"2024-08-02T17:42:53Z","type":"stable","version":"24.8.0"},{"url":"https://github.com/psf/black/releases/tag/24.4.2","date":"2024-04-26T00:31:27Z","type":"stable","version":"24.4.2"},{"url":"https://github.com/psf/black/releases/tag/24.4.1","date":"2024-04-24T15:17:30Z","type":"stable","version":"24.4.1"},{"url":"https://github.com/psf/black/releases/tag/24.4.0","date":"2024-04-12T20:13:48Z","type":"stable","version":"24.4.0"},{"url":"https://github.com/psf/black/releases/tag/24.3.0","date":"2024-03-15T19:35:14Z","type":"stable","version":"24.3.0"},{"url":"https://github.com/psf/black/releases/tag/24.2.0","date":"2024-02-12T20:20:40Z","type":"stable","version":"24.2.0"},{"url":"https://github.com/psf/black/releases/tag/24.1.1","date":"2024-01-28T05:28:09Z","type":"stable","version":"24.1.1"}]` | `[{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-14.3.0","date":"2026-09-27T15:22:48Z","type":"stable","version":"checkstyle-14.3.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-14.2.0","date":"2026-09-27T14:43:29Z","type":"stable","version":"checkstyle-14.2.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-14.1.0","date":"2026-08-30T14:47:48Z","type":"stable","version":"checkstyle-14.1.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-14.0.0","date":"2026-08-18T13:09:20Z","type":"stable","version":"checkstyle-14.0.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.11.0","date":"2026-08-16T21:52:20Z","type":"stable","version":"checkstyle-13.11.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.10.0","date":"2026-08-09T17:48:41Z","type":"stable","version":"checkstyle-13.10.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.9.0","date":"2026-07-27T01:04:59Z","type":"stable","version":"checkstyle-13.9.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.8.0","date":"2026-07-12T02:55:15Z","type":"stable","version":"checkstyle-13.8.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.7.0","date":"2026-06-28T15:13:54Z","type":"stable","version":"checkstyle-13.7.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.6.0","date":"2026-06-15T03:24:52Z","type":"stable","version":"checkstyle-13.6.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.5.0","date":"2026-05-30T20:22:13Z","type":"stable","version":"checkstyle-13.5.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.4.2","date":"2026-05-02T04:07:51Z","type":"stable","version":"checkstyle-13.4.2"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.4.1","date":"2026-04-27T12:43:10Z","type":"stable","version":"checkstyle-13.4.1"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.4.0","date":"2026-03-29T17:41:44Z","type":"stable","version":"checkstyle-13.4.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.3.0","date":"2026-02-28T17:36:40Z","type":"stable","version":"checkstyle-13.3.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.2.0","date":"2026-02-05T20:28:40Z","type":"stable","version":"checkstyle-13.2.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.1.0","date":"2026-01-31T17:26:20Z","type":"stable","version":"checkstyle-13.1.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-13.0.0","date":"2026-01-04T23:48:39Z","type":"stable","version":"checkstyle-13.0.0"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-12.3.1","date":"2025-12-31T15:42:54Z","type":"stable","version":"checkstyle-12.3.1"},{"url":"https://github.com/checkstyle/checkstyle/releases/tag/checkstyle-12.3.0","date":"2025-12-13T15:50:49Z","type":"stable","version":"checkstyle-12.3.0"}]` |
| reliability.status_page | - | yes |
| security.disclosure_policy | yes | - |
| security.scorecard | 7.5 | 7 |
| security.vulnerabilities | `{"count":2,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=pypi&package_name=black&per_page=100","last_12m":1,"max_severity":"HIGH"}` | `{"count":2,"source":"https://advisories.ecosyste.ms/api/v1/advisories?ecosystem=maven&package_name=com.puppycrawl.tools%3Acheckstyle&per_page=100","last_12m":0,"max_severity":"MODERATE"}` |

## Capabilities (Code Quality Tools)

| Capability | Black | Checkstyle |
|---|:--:|:--:|
| **Core** |  |  |
| Function | Formatter | Static analyzer |
| Language scope | Single-language | Single-language |
| Implementation language | Python | Java |
| **Capability** |  |  |
| Autofix | ✓ | ✗ |
| **Config** |  |  |
| Config model | Zero-config | Config file |
| **Extensibility** |  |  |
| Custom rules | ✗ | ✓ |
| **Deployment** |  |  |
| Deployment | Both | CLI-local |
| **Delivery** |  |  |
| Editor integration | ✓ | ✓ |
| CI / VCS gating | ✓ | ✓ |
| **Insight** |  |  |
| Code metrics | ✗ | ✓ |
| **Performance** |  |  |
| Incremental / monorepo aware | ✗ | - |
| **Licensing** |  |  |
| Open-source | OSS | OSS |
| **Commercial** |  |  |
| Pricing model | Free | Free |

*Source: vioscaleAI. Generated 2026-10-16T20:58:48.068Z. "-" = undocumented, not absent.*