AI Models · Open-Source vs Paid

Hermes 4 405B Open vs o4 Mini Paid

Hermes 4 405B vs o4 Mini compared — price per token, context window, multimodality, openness and which to choose. Can the open-source model replace the paid one? Full 2026 breakdown.

Prices & specs refreshed from live data · olud.ai

Open-model prices = cheapest provider via OpenRouter; official maker rates may be higher.

Hermes 4 405BOpenNous Research
$1 /M input
$3 /M outputNo per-token fees if you self-host
TypeOpen-weight
Context window131K tokens
MultimodalNo
Self-hostYes
o4 MiniPaidOpenAI
$1.1 /M input
$4.4 /M outputManaged API (no infra to run)
TypeProprietary
Context window200K tokens
MultimodalYes
Self-hostNo
Choose Hermes 4 405B if you want to self-host, keep your data private and skip per-token fees — it's open-weight and runs on your own hardware. Choose o4 Mini if you want frontier capability through a managed API with zero infrastructure to run.

Hermes 4 405B vs o4 Mini specs

SpecHermes 4 405Bo4 MiniWinner
MakerNous ResearchOpenAI
TypeOpen-weightProprietaryHermes 4 405B
Context window131K tokens200K tokenso4 Mini
Input price$1/M · free self-host$1.1/MHermes 4 405B
Output price$3/M · free self-host$4.4/MHermes 4 405B
Vision / multimodalNoYeso4 Mini
Tool / function callingNoYeso4 Mini
Self-hostableYesNo (API only)Hermes 4 405B
LicenseOpen weightsProprietaryHermes 4 405B

Price gap & when to choose each

Choose Hermes 4 405B if…
  • You want to self-host or run on your cloud
  • You prioritize data privacy & control
  • You want the lowest operating costs
  • You are building open or reproducible AI
Choose o4 Mini if…
  • You want frontier performance through a managed API
  • You need the longer 200K context window
  • You value reliability & ecosystem
  • You don't want to manage infrastructure

Feature comparison

CapabilityHermes 4 405Bo4 Mini
Open weights (downloadable)
Self-hostable
Runs fully offline
Vision / multimodal
Tool / function calling
1M+ context window

Benchmarks: Hermes 4 405B vs o4 Mini

Independent benchmark scores measured by Artificial Analysis. Higher is better (except latency).

Hermes 4 405B
o4 Mini
Intelligence index
7.5
16.7
Math index
69.7
90.7
GPQA
72.7%
78.4%
MMLU-Pro
82.9%
83.2%
Humanity's Last Exam
10.9%
16.5%
Long Context Reasoning
22.3%
61%
LiveCodeBench
68.6%
85.9%
AIME 2025
69.7%
90.7%
IFBench
32.7%
68.7%
τ²-Bench
22.2%
55.6%
Terminal-Bench Hard
11.4%
15.2%
MATH-500
98.9%
AIME
94%
Speed
43.4 tok/s
0 tok/s
Latency
0.74s
0s
Intelligence per $
5
8.7

Benchmark data by Artificial Analysis.

How Hermes 4 405B and o4 Mini score

🏆 Best value & openness: Hermes 4 405B (3.9 vs 3.1 / 5)
CriterionHermes 4 405Bo4 Mini
Cost-efficiency4.04.0
Context window3.54.0
Openness5.01.5
Self-hosting5.01.0
Multimodality2.05.0

Scores come from live data — output price (cost), context length, open vs closed weights (openness & self-hosting) and vision/tool support (multimodality). Raw task quality isn't scored here; it depends on your benchmark — see the verdict.

What each model is

Hermes 4 405B Open

Nous Research · Open-weight

Hermes 4 is a large-scale reasoning model built on Meta-Llama-3.1-405B and released by Nous Research. It introduces a hybrid reasoning mode, where the model can choose to deliberate internally with...

o4 Mini Paid

OpenAI · Proprietary

OpenAI o4-mini is a compact reasoning model in the o-series, optimized for fast, cost-efficient performance while retaining strong multimodal and agentic capabilities. It supports tool use and demonstrates competitive reasoning...

Other models in these families

These variants are tracked but not compared here — one page per family keeps the comparison readable.

Other variants tracked
o4 Mini Higho4 Mini (batch)

Frequently asked questions

Is Hermes 4 405B as good as o4 Mini?

Hermes 4 405B is open-weight and competitive on many tasks, but o4 Mini may still lead on the hardest reasoning and agentic work. The gap keeps narrowing — benchmark both on your actual use case before deciding.

Can I run Hermes 4 405B locally?

Yes. Hermes 4 405B has open weights, so you can self-host it on your own GPUs or run it via a low-cost API. o4 Mini is API-only and cannot be self-hosted.

Hermes 4 405B vs o4 Mini — which should I pick in 2026?

Choose Hermes 4 405B if you want to self-host, keep your data private and skip per-token fees — it's open-weight and runs on your own hardware. Choose o4 Mini if you want frontier capability through a managed API with zero infrastructure to run.

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