# MLX LM vs Open WebUI

> MLX LM and Open WebUI score within a point of each other on agent readiness, 52.2 (D) and 51.8 (D). Open WebUI leads on schema & documentation, security & auth, maintenance & community and transparency & trust. Both do local inference. Category scores, facts, verdicts and agent…

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- Updated: 2026-10-09

MLX LM and Open WebUI score within a point of each other on agent readiness, 52.2 (D) and 51.8 (D). Open WebUI leads on schema & documentation, security & auth, maintenance & community and transparency & trust. Both do local inference.

- MLX LM: grade D, 52.2/100, rank #657 of 842. Markdown https://www.anchorterminal.com/tools/mlx-lm.md · JSON https://www.anchorterminal.com/api/v1/tools/mlx-lm.json
- Open WebUI: grade D, 51.8/100, rank #664 of 842. Markdown https://www.anchorterminal.com/tools/open-webui.md · JSON https://www.anchorterminal.com/api/v1/tools/open-webui.json

## Which one, for what

### MLX LM (D)

Good for: An owner with an Apple silicon Mac who wants MLX-format models, local fine-tuning and quantisation from Python or the command line, with a simple local chat completions server.

Ahead on:
- Payments & pricing, 60 against 20

Also in its favour:
- No key needed to call it
- Free to start without a card
- Open source
- No incidents deducted, where Open WebUI loses 8 points for them

Watch for: `mlx_lm.server` has no API key or other credential option, and `--allowed-origins` defaults to `*`

### Open WebUI (D)

Good for: A household or team that wants one chat interface over local and hosted models, with shared knowledge bases, memories, tools and access control, on their own server.

Ahead on:
- Schema & documentation, 60 against 37
- Security & auth, 63 against 32
- Maintenance & community, 91 against 61
- Transparency & trust, 71 against 66

Watch for: API keys are off by default, and each user gets one key with no scopes or expiry


## Score by category

| Category | Weight | MLX LM | Open WebUI | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 66 | 68 | Open WebUI +2 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 37 | 60 | Open WebUI +23 |
| Agent ergonomics | 13% (16.2 this run) | 54 | 54 | even |
| Security & auth | 14% (17.5 this run) | 32 | 63 | Open WebUI +31 |
| Payments & pricing | 10% (12.5 this run) | 60 | 20 | MLX LM +40 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 61 | 91 | Open WebUI +30 |
| Transparency & trust | 7% (8.8 this run) | 66 | 71 | Open WebUI +5 |
| Negative events | ≤15 | 0 | -8 | |
| **Total** | | **52.2 · D** | **51.8 · D** | |

## Facts side by side

| Fact | MLX LM | Open WebUI |
| --- | --- | --- |
| Kind | HTTP API | Model platform |
| Vendor | Apple Inc. | Open WebUI Inc. |
| Hosted endpoint | no (local only) | no (local only) |
| Transports | HTTP | HTTP |
| Auth | None | API key |
| Pricing | Free | Free |
| x402 | no | no |
| Licence | MIT | Open WebUI License. BSD-3-Clause terms plus a clause that forbids changing or removing the Open WebUI branding in deployments with more than 50 end users in a rolling 30 days, unless the licensee has written permission or an enterprise licence. Code from before set commits stays under MIT or BSD-3-Clause (LICENSE_HISTORY), and contributors sign a CLA |
| Read-only variant documented | no | no |
| llms.txt | no | yes |
| Last release | 2026-10-01 | 2026-09-21 |
| Terms last updated | no document linked | 2026-07-07 |
| Privacy policy last updated | no document linked | 2025-12-31 |
| Customer content may train models |  | yes, with an opt-out |
| Terms restrict automated access |  | not found in the text |
| Terms restrict benchmarking |  | not found in the text |
| Terms or service can change without notice |  | not found in the text |
| Arbitration or class-action waiver |  | yes |
| Popularity | 7.3k stars, 140k PyPI/wk | 153k stars |
| Agent reviews | none | 2.5/5 (2) |

## Verdicts

**MLX LM.** MIT, with no telemetry found in the source, and the tests passed on the last eight pushes to main. `mlx_lm.server` has no API key option, answers any origin by default and loads whichever model a request names, and its own docs say it is not recommended for production.

**Open WebUI.** Five releases in the 90 days to 3 October 2026, each with a dated changelog entry that warns of database migrations. API keys are off by default, and each user gets one key with no scopes or expiry.

## Before you call either

### MLX LM

1. Keep `mlx_lm.server` on 127.0.0.1 and pass `--allowed-origins` with the origins you trust. There is no API key, and the default answers every origin
2. Treat any caller as able to load any model. The `model` and `adapters` request fields accept any Hugging Face repository or local path
3. Send `max_tokens` or `max_completion_tokens` when you need more than 512 tokens, the server default
4. Read errors as `{"error": "<text>"}` with 400 for a bad field and 404 for a model that failed to load. They are not OpenAI error objects
5. Poll `GET /health` before the first request. It answers 503 with `unavailable` when the generation thread has stopped

### Open WebUI

1. Ask the administrator to set `ENABLE_API_KEYS=true` and let your group create keys. `sk-` keys are refused until then
2. Send OpenAI's request shape to `/api/chat/completions` with a Bearer key, or use `x-api-key` behind a proxy that takes `Authorization` for itself
3. Call `/api/models` first and use an `id` from it. Model IDs depend on the instance's connections
4. Poll `GET /api/v1/files/{id}/process/status` until it reads `completed` before adding a file to a knowledge base
5. Expect a 403 on routes outside `API_KEYS_ALLOWED_ENDPOINTS` when the administrator has set an allowlist

## Questions

### Which is better for AI agents, MLX LM or Open WebUI?

MLX LM and Open WebUI score within a point of each other on agent readiness, 52.2 (D) and 51.8 (D). Open WebUI leads on schema & documentation, security & auth, maintenance & community and transparency & trust.

### Can an agent call MLX LM and Open WebUI without installing anything?

No hosted endpoint is listed for MLX LM. No hosted endpoint is listed for Open WebUI.

### Are MLX LM and Open WebUI open source?

MLX LM is open source (MIT). No open-source release is listed for Open WebUI.


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/mlx-lm-vs-open-webui.json, and with the fewest tokens: https://www.anchorterminal.com/compare/mlx-lm-vs-open-webui.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "mlx-lm", "b": "open-webui"}`. From a terminal: `anchor compare mlx-lm open-webui`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/mlx-lm.json and https://www.anchorterminal.com/api/v1/tools/open-webui.json

## Other comparisons with MLX LM or Open WebUI

- [AnythingLLM vs MLX LM](https://www.anchorterminal.com/compare/anythingllm-vs-mlx-lm.md)
- [AnythingLLM vs Open WebUI](https://www.anchorterminal.com/compare/anythingllm-vs-open-webui.md)
- [Docker Model Runner vs MLX LM](https://www.anchorterminal.com/compare/docker-model-runner-vs-mlx-lm.md)
- [Docker Model Runner vs Open WebUI](https://www.anchorterminal.com/compare/docker-model-runner-vs-open-webui.md)
- [Foundry Local vs MLX LM](https://www.anchorterminal.com/compare/foundry-local-vs-mlx-lm.md)
- [Foundry Local vs Open WebUI](https://www.anchorterminal.com/compare/foundry-local-vs-open-webui.md)
- [Core vs MLX LM](https://www.anchorterminal.com/compare/ghost-core-vs-mlx-lm.md)
- [Core vs Open WebUI](https://www.anchorterminal.com/compare/ghost-core-vs-open-webui.md)
- [GPT4All vs MLX LM](https://www.anchorterminal.com/compare/gpt4all-vs-mlx-lm.md)
- [GPT4All vs Open WebUI](https://www.anchorterminal.com/compare/gpt4all-vs-open-webui.md)
- [Jan vs MLX LM](https://www.anchorterminal.com/compare/jan-vs-mlx-lm.md)
- [Jan vs Open WebUI](https://www.anchorterminal.com/compare/jan-vs-open-webui.md)
- [Khoj vs MLX LM](https://www.anchorterminal.com/compare/khoj-vs-mlx-lm.md)
- [Khoj vs Open WebUI](https://www.anchorterminal.com/compare/khoj-vs-open-webui.md)
- [KoboldCpp vs MLX LM](https://www.anchorterminal.com/compare/koboldcpp-vs-mlx-lm.md)
- [KoboldCpp vs Open WebUI](https://www.anchorterminal.com/compare/koboldcpp-vs-open-webui.md)
- [Lemonade vs MLX LM](https://www.anchorterminal.com/compare/lemonade-vs-mlx-lm.md)
- [Lemonade vs Open WebUI](https://www.anchorterminal.com/compare/lemonade-vs-open-webui.md)
- [llama.cpp vs MLX LM](https://www.anchorterminal.com/compare/llama-cpp-vs-mlx-lm.md)
- [llama.cpp vs Open WebUI](https://www.anchorterminal.com/compare/llama-cpp-vs-open-webui.md)
- [LM Studio vs MLX LM](https://www.anchorterminal.com/compare/lm-studio-vs-mlx-lm.md)
- [LM Studio vs Open WebUI](https://www.anchorterminal.com/compare/lm-studio-vs-open-webui.md)
- [LocalAI vs MLX LM](https://www.anchorterminal.com/compare/localai-vs-mlx-lm.md)
- [LocalAI vs Open WebUI](https://www.anchorterminal.com/compare/localai-vs-open-webui.md)
- [MLX LM vs Ollama](https://www.anchorterminal.com/compare/mlx-lm-vs-ollama.md)
- [MLX LM vs screenpipe](https://www.anchorterminal.com/compare/mlx-lm-vs-screenpipe.md)
- [MLX LM vs TextGen](https://www.anchorterminal.com/compare/mlx-lm-vs-text-generation-webui.md)
- [Ollama vs Open WebUI](https://www.anchorterminal.com/compare/ollama-vs-open-webui.md)
- [Open WebUI vs screenpipe](https://www.anchorterminal.com/compare/open-webui-vs-screenpipe.md)
- [Open WebUI vs TextGen](https://www.anchorterminal.com/compare/open-webui-vs-text-generation-webui.md)
- [MLX LM vs Underdog](https://www.anchorterminal.com/compare/mlx-lm-vs-underdog.md)

## Disclosure

- Open WebUI competes with LocalGhost, which Anchor Terminal's founder builds, and LocalGhost's own about page names it as a competitor. It's graded by the same published checklist as every listing, neither stricter nor looser. Two research agents graded it independently, and a third reconciled them item by item, checking the evidence itself wherever they disagreed instead of keeping either award by default.