AI Models · Open-Source vs Paid

Hermes 4 405B Open vs Claude Opus 5 Paid

Hermes 4 405B vs Claude Opus 5 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
Claude Opus 5PaidAnthropic
$5 /M input
$25 /M outputManaged API (no infra to run)
TypeProprietary
Context window1M 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 Claude Opus 5 if you want frontier capability through a managed API with zero infrastructure to run.

Hermes 4 405B vs Claude Opus 5 specs

SpecHermes 4 405BClaude Opus 5Winner
MakerNous ResearchAnthropic
TypeOpen-weightProprietaryHermes 4 405B
Context window131K tokens1M tokensClaude Opus 5
Input price$1/M · free self-host$5/MHermes 4 405B
Output price$3/M · free self-host$25/MHermes 4 405B
Vision / multimodalNoYesClaude Opus 5
Tool / function callingNoYesClaude Opus 5
Self-hostableYesNo (API only)Hermes 4 405B
LicenseOpen weightsProprietaryHermes 4 405B

Price gap & when to choose each

8.3×cheaper per output token

Hermes 4 405B is ~8.3× cheaper than Claude Opus 5 on output tokens ($3 vs $25 per M tokens).

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 Claude Opus 5 if…
  • You want frontier performance through a managed API
  • You need the longer 1M context window
  • You value reliability & ecosystem
  • You don't want to manage infrastructure

Feature comparison

CapabilityHermes 4 405BClaude Opus 5
Open weights (downloadable)
Self-hostable
Runs fully offline
Vision / multimodal
Tool / function calling
1M+ context window

Benchmarks: Hermes 4 405B vs Claude Opus 5

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

Hermes 4 405B
Claude Opus 5
Intelligence index
7.5
50.7
Math index
69.7
GPQA
72.7%
93.2%
MMLU-Pro
82.9%
Humanity's Last Exam
10.9%
54.9%
Long Context Reasoning
22.3%
79.3%
LiveCodeBench
68.6%
AIME 2025
69.7%
IFBench
32.7%
τ²-Bench
22.2%
Terminal-Bench Hard
11.4%
Coding index
78
SciCode
56.4%
τ-Bench Banking
42.1%
Terminal-Bench
89.1%
Speed
43.4 tok/s
61.4 tok/s
Latency
0.74s
36.03s
Intelligence per $
5
5.1

Benchmark data by Artificial Analysis.

How Hermes 4 405B and Claude Opus 5 score

🏆 Best value & openness: Hermes 4 405B (3.9 vs 3.1 / 5)
CriterionHermes 4 405BClaude Opus 5
Cost-efficiency4.03.0
Context window3.55.0
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...

Claude Opus 5 Paid

Anthropic · Proprietary

Claude Opus 5 is Anthropic’s flagship model for demanding reasoning, coding, and long-horizon agentic work. It is particularly strong at end-to-end software tasks, code review and bug finding, visual analysis...

Other models in these families

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

Other variants tracked
Claude Opus 5 (batch)Claude Opus 4.8Claude Opus 4.8 (batch)Claude Opus 4.7Claude Opus 4.7 (batch)Claude Opus 4.6Claude Opus 4.6 (batch)Claude Opus 4.5Claude Opus 4.5 (batch)Claude Opus 4.1Claude Opus 4.1 (batch)Claude Opus 4

Frequently asked questions

Is Hermes 4 405B as good as Claude Opus 5?

Hermes 4 405B is open-weight and competitive on many tasks, but Claude Opus 5 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. Claude Opus 5 is API-only and cannot be self-hosted.

How much cheaper is Hermes 4 405B?

Hermes 4 405B costs $3/M output vs $25/M for Claude Opus 5 — roughly 8x cheaper via API, and free if you self-host.

Hermes 4 405B vs Claude Opus 5 — 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 Claude Opus 5 if you want frontier capability through a managed API with zero infrastructure to run.

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