Hermes 3 Llama 3.1 405b
Nous Research's flagship 405B open-weights model, fine-tuned for advanced agentic reasoning, structured JSON, and unmatched steerability.
Get API key- Provider
- Nous Research
- Price
- $1.10 in · $3 out / 1M
- Context window
- 128K tokens
- Released
- August 16, 2024
- License
- Llama 3.1 Community License
What is Hermes 3 Llama 3.1 405b?
Hermes 3 Llama 3.1 405B is a frontier-class, open-weights model developed by Nous Research. Built as a full-parameter fine-tune of Meta's Llama 3.1 405B, it is optimized for highly steerable roleplay, complex agentic reasoning, multi-turn conversations, and reliable structured JSON outputs.
Use it privately on Venice
On Venice, you can run this massive 405-billion-parameter model with absolute privacy and zero prompt retention. Venice routes your requests anonymously, ensuring your proprietary code, complex agentic workflows, and personal prompts are never stored, profiled, or used to train third-party models.
What can it do?
- •Frontier-level reasoning and agentic capabilities powered by a massive 405B parameter architecture.
- •Extreme steerability, allowing users to define highly complex system prompts, personas, and custom behaviors.
- •Superb structured outputs, native JSON schema support, and reliable function calling.
- •Excellent long-context coherence and multi-turn conversation tracking.
- •High computational footprint makes inference slower and more resource-intensive than smaller models.
- •Lacks native multimodal capabilities (text-only input and output).
- •FP8 quantization on Venice may introduce minor precision trade-offs compared to full 16-bit precision.
Hermes 3 Llama 3.1 405b capabilities
- Tool use / function calling
- Vision (image input)
- Reasoning
- Web search
- Code-optimized
- Structured output (JSON schema)
- Audio input
- Video input
- Multiple image inputs
- Log probabilities
How to use it via API
Venice exposes an OpenAI-compatible API. Swap your base URL and call hermes-3-llama-3.1-405b.
curl https://api.venice.ai/api/v1/chat/completions \
-H "Authorization: Bearer $VENICE_API_KEY" \
-H "Content-Type: application/json" \
-d '{
"model": "hermes-3-llama-3.1-405b",
"messages": [{ "role": "user", "content": "Explain quantum tunneling simply." }]
}'Specifications
Pricing
Billed per token on Venice: $1.10 per 1M input tokens and $3 per 1M output tokens.
New Venice accounts include a free daily allowance and 500 welcome credits — no credit card required.
Hermes 3 Llama 3.1 405b vs alternatives
| Model | Context window | Strongest at | Open weights | Price (Venice) |
|---|---|---|---|---|
| Hermes 3 Llama 3.1 405b | 128K tokens | Agentic reasoning & steerability | Yes | $1.10 / $3 |
| DeepSeek V3.2 | 160K tokens | Coding & math efficiency | Yes | $0.33 / $0.48 |
| Grok 4.3 | 1M tokens | Real-time info & reasoning | No | $1.42 / $2.83 |
| Claude Opus 4.8 | 1M tokens | Deep analysis & writing | No | $6 / $30 |
Nous Research's flagship open-weights giant, optimized for steerability.
What is it good for?
- •Complex multi-turn agentic workflows and synthetic data generation.
- •Highly customized roleplaying, conversational simulation, and creative writing.
- •Structured data extraction and reliable JSON generation from unstructured text.
- •Advanced coding assistance, code generation, and system-level debugging.
Prompting tips
- •Use ChatML formatting and explicit system prompts to take full advantage of the model's steerability.
- •Provide clear JSON schemas when utilizing its structured output capabilities for consistent parsing.
- •Enable Venice's web search capability to ground its reasoning in real-time, up-to-date information.
Version history
Highly popular lightweight agentic model.
Mid-sized flagship offering a balance of speed and intelligence.
CurrentCurrent flagship full-parameter fine-tune.
Frequently asked questions
Hermes 3 Llama 3.1 405B is a frontier-class, open-weights language model fine-tuned by Nous Research on top of Meta's Llama 3.1 405B. It is designed for advanced reasoning, agentic workflows, structured outputs, and highly customizable roleplay.
On Venice, Hermes 3 Llama 3.1 405B is priced at $1.10 per 1 million input tokens and $3.00 per 1 million output tokens, offering frontier-level intelligence at a fraction of the cost of proprietary rivals.
Hermes 3 is an open-weights model released under the Llama 3.1 Community License. While it is free to download and self-host if you have the massive hardware required, Venice provides convenient, pay-as-you-go API access.
Yes, Hermes 3 has native support for structured function calling and tool use. On Venice, it is integrated with web search capabilities to ground its responses in real-time information.
Hermes 3 405b excels at extreme steerability, roleplay, and complex agentic workflows. DeepSeek V3.2 is highly efficient, cheaper, and exceptionally strong at math and coding. Choose Hermes 3 for highly customized personas and DeepSeek for raw technical tasks.
Venice operates under a strict zero-retention policy. Your prompts and generations are processed anonymously, are never stored, and are never used to train AI models, giving you complete sovereignty over your data.
On Venice, Hermes 3 Llama 3.1 405B supports a context window of 128K tokens, allowing you to process large documents, extensive codebases, or long conversational histories.
Related models
Run Hermes 3 Llama 3.1 405b privately.
No prompt logging. No data used for training. Free to start — no credit card.
