Hermes 4 405B
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...
Updated 37 min ago · first seen 11 Sept 2026
model_01M294WWCJVDMXVJBDYQJNKGPQ
- Context
- 131.1K tokens
- T2 · 37 min ago
- Released
- 26 Aug 2025
- T2 · 4 h ago
- Knowledge cutoff
- Aug 2024
- T2 · 4 h ago
Specification
- Release date
- 26 Aug 2025
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Openness
- open-weights
Source:Artificial AnalysisT2observed 2 h agomedium
- Context window
- 131.1K tokens
Source:OpenRouter public model & pricing listingT2observed 37 min agomedium
- Max output
- 118K tokens
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Knowledge cutoff
- Aug 2024
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Modalities
- text
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Input modalities
- text
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Output modalities
- text
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Hugging Face repo
- NousResearch/Hermes-4-405B
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Aa median output tokens per second
- 43.1
Source:Artificial AnalysisT2observed 2 h agomedium
- Openrouter id
- nousresearch/hermes-4-405b
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Supported parameters
- frequency_penalty, include_reasoning, max_tokens, presence_penalty, reasoning, repetition_penalty, response_format, temperature, top_k, top_p
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
Each value shows its source, tier and observation time. Conflicting claims are kept side by side and flagged — never averaged. How AI Atlas records facts →
Provenance
Attributed facts
16
Source tiers
T216
Freshest observation
37 min ago
Conflicts
None
Modalities
- Modalities
- text
- Input
- text
- Output
- text
Capabilities
Tool calling
No
OpenRouter public model & pricing listing · T2
Structured output
Yes
OpenRouter public model & pricing listing · T2
Reasoning
Yes
OpenRouter public model & pricing listing · T2
Vision
Unavailable
Audio
Unavailable
Fine-tuning available
Unavailable
- Context window
- 131.1K tokens
Source:OpenRouter public model & pricing listingT2observed 37 min agomedium
- Max output
- 118K tokens
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
- Knowledge cutoff
- Aug 2024
Source:OpenRouter public model & pricing listingT2observed 4 h agomedium
| Benchmark | Score | Metric | Config | Evaluated | Source |
|---|---|---|---|---|---|
| τ²-bench | 22.22% | pass^1 | aa_slug=hermes-4-llama-3-1-405b-reasoning · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| Artificial Analysis Intelligence Index | 7.49 | index | aa_slug=hermes-4-llama-3-1-405b-reasoning · version=4.3 · estimated=true | — | artificialanalysis.aiT2 |
| GPQA | 72.73% | accuracy | aa_slug=hermes-4-llama-3-1-405b-reasoning · variant=GPQA Diamond · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| Humanity's Last Exam | 10.89% | accuracy | aa_slug=hermes-4-llama-3-1-405b-reasoning · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| IFBench | 32.72% | accuracy | aa_slug=hermes-4-llama-3-1-405b-reasoning · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| Terminal-Bench | 11.36% | accuracy | aa_slug=hermes-4-llama-3-1-405b-reasoning · variant=hard · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
Scores are reported as published, with their evaluation configuration (harness, prompting, judge). Results with different configs are not directly comparable — see methodology.
Current prices
| Provider | Input / 1M | Output / 1M | Cached in | Batch in / out | Context | Observed | Source |
|---|---|---|---|---|---|---|---|
| OpenRouternousresearch/hermes-4-405b | $1 | $3 | — | — | 131.1K | 37 min ago | openrouter.aiT2 |
USD per 1M tokens as published by each provider (USD). Rows are append-only: every change is kept in the history below.
Available through 1
Price history
Input price · USD / 1M tokens
Output price · USD / 1M tokens
- OpenRouter
No hardware estimate available
No lineage recorded
Papers 0
No papers linked yet.
Repositories 0
No repositories linked yet.
As of
Rewind the record: see this entity's attributes exactly as AI Atlas knew them on a given day.
Claim history · Context window
Context windowcontext_length3
| Value | Valid from → to | Status | Source | Confidence | Extractor |
|---|---|---|---|---|---|
| 131.1K tokens | → current | current | OpenRouter public model & pricing listingT2 | medium | deterministic |
| 128K tokens | → | superseded | Artificial AnalysisT2 | medium | deterministic |
| 131.1K tokens | → | superseded | OpenRouter public model & pricing listingT2 | medium | deterministic |
Claims are temporal and append-only: a new observation closes the previous claim (valid_to) instead of overwriting it. Conflicting claims from different sources are kept side by side and flagged — never averaged. Methodology →
Hermes 4 405B: context length changed from 128000 to 131072
Context window128K tokens→131.1K tokensopenrouterHermes 4 405B scores 11.36% on Terminal-Bench
artificial_analysisHermes 4 405B scores 22.22% on τ²-bench
artificial_analysisHermes 4 405B scores 32.72% on IFBench
artificial_analysisHermes 4 405B scores 10.89% on Humanity's Last Exam
artificial_analysisHermes 4 405B scores 72.73% on GPQA
artificial_analysisHermes 4 405B scores 7.49 on Artificial Analysis Intelligence Index
artificial_analysisHermes 4 405B: context length changed from 131072 to 128000
Context window131.1K tokens→128K tokensartificial_analysisOpenRouter lists Hermes 4 405B at $1 in / $3 out per 1M tokens
openrouter
| Source | Document | Type | Tier | Last observed | Snapshots |
|---|---|---|---|---|---|
| OpenRouter public model & pricing listing | openrouter.ai/api/v1/models | catalogue | T2· Quality secondary | 37 min ago | 3 |
| Artificial Analysis | artificialanalysis.ai/leaderboards/models | leaderboard | T2· Quality secondary | 2 h ago | 1 |
Tier 1 = official/primary, 2 = quality secondary, 3 = community, 4 = unverified. Every snapshot is archived; see all sources and the methodology.