Nous: Hermes 4 405B

Text input Text output
Author's Description

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...

Key Specifications
Cost
$$$$
Context
131K
Parameters
405B
Released
Aug 26, 2025
Speed
Ability
Reliability
Supported Parameters

This model supports the following parameters:

Temperature Include Reasoning Reasoning Presence Penalty Max Tokens Response Format Frequency Penalty Top P
Features

This model supports the following features:

Reasoning Response Format
Performance Summary

Nous: Hermes 4 405B demonstrates competitive response times, ranking in the 59th percentile across various benchmarks, and offers moderate pricing, positioned in the 39th percentile. A standout feature is its exceptional reliability, achieving a 100% success rate across all evaluated benchmarks, indicating robust technical stability. The model excels in specific areas, achieving perfect accuracy in both Hallucinations (100%) and Ethics (100%) benchmarks, highlighting its strong alignment and ability to acknowledge uncertainty. It also shows strong performance in General Knowledge (99.5%) and Email Classification (99.0%), indicating broad utility in information retrieval and categorization tasks. Its hybrid reasoning mode, allowing internal deliberation, likely contributes to its strong performance in these areas. However, Hermes 4 exhibits some weaknesses. Its Instruction Following accuracy is 61.0%, suggesting room for improvement in handling complex, multi-layered directives. Similarly, its Mathematics accuracy (79.0%) and Reasoning accuracy (72.0%) are in the lower percentiles, indicating that while it has an expanded post-training corpus emphasizing reasoning, there are still challenges in advanced problem-solving. Coding performance is moderate at 83.0%. Overall, Hermes 4 is a reliable and ethically sound model with strong general knowledge and classification capabilities, but its performance in complex instruction following and advanced mathematical/logical reasoning could be further enhanced.

Model Pricing

Current Pricing

Feature Price (per 1M tokens)
Prompt $1
Completion $3

Price History

Available Endpoints
Provider Endpoint Name Context Length Pricing (Input) Pricing (Output)
Nebius
Nebius | nousresearch/hermes-4-405b 131K $1 / 1M tokens $3 / 1M tokens
Chutes
Chutes | nousresearch/hermes-4-405b 131K $1 / 1M tokens $3 / 1M tokens
Benchmark Results
Benchmark Category Reasoning Strategy Free Executions Accuracy Cost Duration
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