---
title: "DeepSpeed vs FastChat"
type: "comparison"
canonical_url: "https://www.graphcanon.com/compare/deepspeedai-deepspeed-vs-lm-sys-fastchat"
tools: ["deepspeedai-deepspeed", "lm-sys-fastchat"]
---

# DeepSpeed vs FastChat

*GraphCanon updated Jul 11, 2026*

## Verdict

Pick DeepSpeed if decisions for DeepSpeed use are driven by its capacity to handle large models efficiently using techniques such as data parallelism, model parallelism, pipeline parallelism, and compression; pick FastChat if fastChat is a comprehensive open platform for managing large language models (LLMs) that includes capabilities for training, serving, evaluating, and comparing chatbot models via web UIs and RESTful.

[DeepSpeed](https://www.deepspeed.ai/) reports 43k GitHub stars, 4.9k forks, and 1.3k open issues, last pushed Jul 11, 2026. [FastChat](https://github.com/lm-sys/FastChat) has 39k stars, 4.8k forks, and 1.0k open issues, last pushed May 1, 2026. Figures are from public GitHub metadata via [DeepSpeed's repository](https://github.com/deepspeedai/DeepSpeed) and [FastChat's repository](https://github.com/lm-sys/FastChat).

| | [DeepSpeed](/tools/deepspeedai-deepspeed.md) | [FastChat](/tools/lm-sys-fastchat.md) |
| --- | --- | --- |
| Tagline | Deep learning optimization library for efficient distributed training and inference | An open platform for training, serving, and evaluating large language models |
| Stars | 42,685 | 39,490 |
| Forks | 4,883 | 4,788 |
| Open issues | 1,302 | 1,027 |
| Language | Python | Python |
| Adopt for | Decisions for DeepSpeed use are driven by its capacity to handle large models efficiently using techniques such as data parallelism, model parallelism, pipeline parallelism, and compression. | FastChat is a comprehensive open platform for managing large language models (LLMs) that includes capabilities for training, serving, evaluating, and comparing chatbot models via web UIs and RESTful APIs. It powers ChatB |
| Persona | - | - |
| Runtime | - | - |
| License | Apache-2.0 | Apache-2.0 |
| Categories | Inference & Serving, Model Training | Evaluation & Observability, Inference & Serving, LLM Frameworks, Model Training |

## Trust and health

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

| | [DeepSpeed](/tools/deepspeedai-deepspeed.md) | [FastChat](/tools/lm-sys-fastchat.md) |
| --- | --- | --- |
| Maintenance | Very active (96%) | Steady (60%) |
| Days since push | 0d | 71d |
| Open issues (now) | 1.3k | 1.0k |
| Full report | [trust report](/tools/deepspeedai-deepspeed/trust.md) | [trust report](/tools/lm-sys-fastchat/trust.md) |

## Decision facts: DeepSpeed

- **Adopt for:** Decisions for DeepSpeed use are driven by its capacity to handle large models efficiently using techniques such as data parallelism, model parallelism, pipeline parallelism, and compression.

## Decision facts: FastChat

- **Adopt for:** FastChat is a comprehensive open platform for managing large language models (LLMs) that includes capabilities for training, serving, evaluating, and comparing chatbot models via web UIs and RESTful APIs. It powers ChatB

## Choose when

### Choose DeepSpeed if…

- Tags unique to DeepSpeed: billion-parameters, compression, data-parallelism, deep-learning.
- - When training or inferring with PyTorch on large datasets or complex deep learning models (up to trillion parameters)
- More GitHub stars (43k vs 39k) - visibility, not fit.

### Choose FastChat if…

- Tags unique to FastChat: chatbots, distributed serving, evaluation system, large-language-models.
- Also covers Evaluation & Observability, LLM Frameworks.
- - You are looking to train and evaluate state-of-the-art models such as Vicuna or MT-Bench.

## When NOT to use DeepSpeed

- - When you are working in an environment that only supports CPU-based training without access to CUDA or ROCm compatible GPUs
- - If your project's PyTorch version is less than 2.0, DeepSpeed may not support all of its features and optimizations effectively

## When NOT to use FastChat

- - You require a proprietary or closed-source framework; FastChat is open-source under Apache-2.0 license and its use might be unsuitable for environments requiring proprietary solutions.
- - Your chatbot evaluation needs do not align with the types of data used in FastChat's datasets (e.g., human votes, MT-Bench evaluations).
- - You prefer a more user-friendly setup without the need to clone a repository and manually install dependencies; FastChat requires installation from source with additional steps for Rust and CMake on
- + Mac.

## Common questions

### What is the difference between DeepSpeed and FastChat?

DeepSpeed: Deep learning optimization library for efficient distributed training and inference. FastChat: An open platform for training, serving, and evaluating large language models. See the comparison table for live GitHub stats and shared categories.

### When should I choose DeepSpeed over FastChat?

Choose DeepSpeed over FastChat when Tags unique to DeepSpeed: billion-parameters, compression, data-parallelism, deep-learning; - When training or inferring with PyTorch on large datasets or complex deep learning models (up to trillion parameters); More GitHub stars (43k vs 39k) - visibility, not fit.

### When should I choose FastChat over DeepSpeed?

Choose FastChat over DeepSpeed when Tags unique to FastChat: chatbots, distributed serving, evaluation system, large-language-models; Also covers Evaluation & Observability, LLM Frameworks; - You are looking to train and evaluate state-of-the-art models such as Vicuna or MT-Bench.

### When should I avoid DeepSpeed?

- When you are working in an environment that only supports CPU-based training without access to CUDA or ROCm compatible GPUs - If your project's PyTorch version is less than 2.0, DeepSpeed may not support all of its features and optimizations effectively

### When should I avoid FastChat?

- You require a proprietary or closed-source framework; FastChat is open-source under Apache-2.0 license and its use might be unsuitable for environments requiring proprietary solutions. - Your chatbot evaluation needs do not align with the types of data used in FastChat's datasets (e.g., human votes, MT-Bench evaluations). - You prefer a more user-friendly setup without the need to clone a repository and manually install dependencies; FastChat requires installation from source with additional steps for Rust and CMake on + Mac.

### Is DeepSpeed or FastChat more popular on GitHub?

DeepSpeed has more GitHub stars (42,685 vs 39,490). Stars measure visibility, not whether either tool fits your constraints.

### Are DeepSpeed and FastChat open source?

Yes - both are open-source projects on GitHub (DeepSpeed: Apache-2.0, FastChat: Apache-2.0).

### Where can I find alternatives to DeepSpeed or FastChat?

GraphCanon lists graph-backed alternatives at [DeepSpeed alternatives](/tools/deepspeedai-deepspeed/alternatives) and [FastChat alternatives](/tools/lm-sys-fastchat/alternatives) ([DeepSpeed markdown twin](/tools/deepspeedai-deepspeed/alternatives.md), [FastChat markdown twin](/tools/lm-sys-fastchat/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/deepspeedai-deepspeed-vs-lm-sys-fastchat.md) mirrors this page for agents and LLM crawlers, with the same stats table and FAQ answers.

### Which is better maintained, DeepSpeed or FastChat?

DeepSpeed: Very active. FastChat: Steady. 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 DeepSpeed and FastChat?

GraphCanon publishes per-repo trust reports with dated maintenance, provenance, and scan summaries: [DeepSpeed trust report](/tools/deepspeedai-deepspeed/trust); [FastChat trust report](/tools/lm-sys-fastchat/trust).

---

**Machine-readable endpoints**

- JSON: [`/api/graphcanon/graph?tool=deepspeedai-deepspeed`](/api/graphcanon/graph?tool=deepspeedai-deepspeed)
- 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/_
