---
title: "auto-sklearn vs HPOBench"
type: "comparison"
canonical_url: "https://www.graphcanon.com/compare/automl-auto-sklearn-vs-automl-hpobench"
tools: ["automl-auto-sklearn", "automl-hpobench"]
---

# auto-sklearn vs HPOBench

*GraphCanon updated Aug 4, 2026*

## Verdict

Pick auto-sklearn if auto-sklearn is an automated machine learning toolkit designed to automate hyperparameter optimization and function seamlessly with scikit-learn workflows; pick HPOBench if hPOBench is useful for researchers and developers working on hyperparameter optimization techniques in automated machine learning scenarios.

[auto-sklearn](https://automl.github.io/auto-sklearn) reports 8.1k GitHub stars, 1.3k forks, and 209 open issues, last pushed Jun 29, 2026. [HPOBench](https://github.com/automl/HPOBench) has 170 stars, 36 forks, and 34 open issues, last pushed May 21, 2025. Figures are from public GitHub metadata via [auto-sklearn's repository](https://github.com/automl/auto-sklearn) and [HPOBench's repository](https://github.com/automl/HPOBench).

| | [auto-sklearn](/tools/automl-auto-sklearn.md) | [HPOBench](/tools/automl-hpobench.md) |
| --- | --- | --- |
| Tagline | Automated Machine Learning with scikit-learn | A collection of hyperparameter optimization benchmark problems |
| Stars | 8,127 | 170 |
| Forks | 1,327 | 36 |
| Open issues | 209 | 34 |
| Language | Python | Python |
| Adopt for | auto-sklearn is an automated machine learning toolkit designed to automate hyperparameter optimization and function seamlessly with scikit-learn workflows. | HPOBench is useful for researchers and developers working on hyperparameter optimization techniques in automated machine learning scenarios. |
| Persona | - | - |
| Runtime | - | - |
| License | BSD-3-Clause | HPOBench is open source under the Apache-2.0 license. |
| Categories | Model Training | Model Training |

## Trust and health

_Sourced signals - not a safety guarantee. No winner column._

| | [auto-sklearn](/tools/automl-auto-sklearn.md) | [HPOBench](/tools/automl-hpobench.md) |
| --- | --- | --- |
| Maintenance | Steady (60%) | Dormant (18%) |
| Days since push | 35d | 439d |
| Open issues (now) | 209 | 34 |
| Full report | [trust report](/tools/automl-auto-sklearn/trust.md) | [trust report](/tools/automl-hpobench/trust.md) |

## Shared compatibility

- **Python**: [auto-sklearn](/tools/automl-auto-sklearn.md) - Python runtime; [HPOBench](/tools/automl-hpobench.md) - Python runtime

## Decision facts: auto-sklearn

- **Adopt for:** auto-sklearn is an automated machine learning toolkit designed to automate hyperparameter optimization and function seamlessly with scikit-learn workflows.

## Decision facts: HPOBench

- **Pricing:** freemium
- **Requirements:** The installation recommends, but does not strictly require singularity version 3.6, which can be an additional setup step.
- **Adopt for:** HPOBench is useful for researchers and developers working on hyperparameter optimization techniques in automated machine learning scenarios.
- **License detail:** HPOBench is open source under the Apache-2.0 license.

## Choose when

### Choose auto-sklearn if…

- License: auto-sklearn is BSD-3-Clause, HPOBench is Apache-2.0.
- Tags unique to auto-sklearn: automated-machine-learning, hyperparameter-search, hyperparameter-tuning, meta-learning.
- auto-sklearn ships Docker support for self-hosted deployment.
- When you need a drop-in replacement estimator for your existing scikit-learn pipeline that can handle the complexity of hyperparameter tuning automatically.

### Choose HPOBench if…

- License: HPOBench is Apache-2.0, auto-sklearn is BSD-3-Clause.
- Requirements: The installation recommends, but does not strictly require singularity version 3.6, which can be an additional setup step..
- Tags unique to HPOBench: benchmark, python.
- When you are specifically interested in benchmarking hyperparameter optimization problems that include containerized benchmarks to ensure consistency across environments.

## When NOT to use auto-sklearn

- If extensive customization or control over individual machine learning components is required beyond what auto-sklearn's automation offers.
- In cases requiring non-scikit-learn model ensembles, as the toolkit primarily supports models that are part of the scikit-earn library.

## When NOT to use HPOBench

- Avoid HPOBench if your project does not require Python or you are looking for a platform that exclusively focuses on the automation of model selection without hyperparameter optimization.
- If you prefer tools with built-in support for multiple programming languages, rather than focusing solely on Python as is the case with HPOBench.

## Common questions

### What is the difference between auto-sklearn and HPOBench?

auto-sklearn: Automated Machine Learning with scikit-learn. HPOBench: A collection of hyperparameter optimization benchmark problems. See the comparison table for live GitHub stats and shared categories.

### When should I choose auto-sklearn over HPOBench?

Choose auto-sklearn over HPOBench when License: auto-sklearn is BSD-3-Clause, HPOBench is Apache-2.0; Tags unique to auto-sklearn: automated-machine-learning, hyperparameter-search, hyperparameter-tuning, meta-learning; auto-sklearn ships Docker support for self-hosted deployment; When you need a drop-in replacement estimator for your existing scikit-learn pipeline that can handle the complexity of hyperparameter tuning automatically.

### When should I choose HPOBench over auto-sklearn?

Choose HPOBench over auto-sklearn when License: HPOBench is Apache-2.0, auto-sklearn is BSD-3-Clause; Requirements: The installation recommends, but does not strictly require singularity version 3.6, which can be an additional setup step.; Tags unique to HPOBench: benchmark, python; When you are specifically interested in benchmarking hyperparameter optimization problems that include containerized benchmarks to ensure consistency across environments.

### When should I avoid auto-sklearn?

If extensive customization or control over individual machine learning components is required beyond what auto-sklearn's automation offers. In cases requiring non-scikit-learn model ensembles, as the toolkit primarily supports models that are part of the scikit-earn library.

### When should I avoid HPOBench?

Avoid HPOBench if your project does not require Python or you are looking for a platform that exclusively focuses on the automation of model selection without hyperparameter optimization. If you prefer tools with built-in support for multiple programming languages, rather than focusing solely on Python as is the case with HPOBench.

### Is auto-sklearn or HPOBench more popular on GitHub?

auto-sklearn has more GitHub stars (8,127 vs 170). Stars measure visibility, not whether either tool fits your constraints.

### Are auto-sklearn and HPOBench open source?

Yes - both are open-source projects on GitHub (auto-sklearn: BSD-3-Clause, HPOBench: Apache-2.0).

### Where can I find alternatives to auto-sklearn or HPOBench?

GraphCanon lists graph-backed alternatives at [auto-sklearn alternatives](/tools/automl-auto-sklearn/alternatives) and [HPOBench alternatives](/tools/automl-hpobench/alternatives) ([auto-sklearn markdown twin](/tools/automl-auto-sklearn/alternatives.md), [HPOBench markdown twin](/tools/automl-hpobench/alternatives.md)), ranked by typed relationship edges rather than popularity votes.

### Is there a machine-readable version of this comparison?

Yes. The markdown twin at [this comparison](/compare/automl-auto-sklearn-vs-automl-hpobench.md) mirrors this page for agents and LLM crawlers, with the same stats table and FAQ answers.

### Which is better maintained, auto-sklearn or HPOBench?

auto-sklearn: Steady. HPOBench: Dormant. Compare maintenance labels, days since push, and release cadence in the trust section below - stars alone do not measure maintenance.

### Where are the full trust reports for auto-sklearn and HPOBench?

GraphCanon publishes per-repo trust reports with dated maintenance, provenance, and scan summaries: [auto-sklearn trust report](/tools/automl-auto-sklearn/trust); [HPOBench trust report](/tools/automl-hpobench/trust).

---

**Machine-readable endpoints**

- JSON: [`/api/graphcanon/graph?tool=automl-auto-sklearn`](/api/graphcanon/graph?tool=automl-auto-sklearn)
- LLM index: [/llms.txt](/llms.txt)
- Full corpus: [/llms-full.txt](/llms-full.txt)

_GraphCanon - The knowledge graph for AI development. https://www.graphcanon.com/_
