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Hermes 4 405B

Open weight

Nous Research · Released August 2025 · Knowledge cutoff August 2024

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...

Facts and pricing

Provider
Nous Research
Context window
131K tokens
Input price
11.0 credits / 1M tokens ($1.00 raw)
Output price
33.0 credits / 1M tokens ($3.00 raw)
Vision (image input)
No
Tool calling
No
Extended reasoning
No

Credits are what Zeplik bills: 1 credit = $0.10, computed from the raw provider rate with a 1.10x margin. Raw prices shown per 1M tokens.

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What Hermes 4 405B is best for

Nous Research family

ModelContextInput cr/MOutput cr/MReleased
Hermes 4 405B131K11.033.0August 2025
Hermes 3 70B Instruct131K7.77.7August 2024
Hermes 3 405B Instruct131K11.011.0August 2024

Frequently asked questions

What is Hermes 4 405B?
Hermes 4 405B is an AI model by Nous Research. 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...
How much does Hermes 4 405B cost on Zeplik?
Input tokens cost 11.0 credits per million and output tokens 33.0 credits per million (1 credit = $0.10; the raw provider rates are $1.00 and $3.00 per million). New accounts start with free credits.
How long can a conversation with Hermes 4 405B be?
Hermes 4 405B has a 131K-token context window (131,072 tokens), which covers the conversation plus any documents you attach.
Does Hermes 4 405B support images and tools?
Hermes 4 405B is text-only and does not support tool calling.

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More you can do with Hermes 4 405B

Hermes 4 405B - Nous Research AI Model | Zeplik Chat