Hermes 4
Nous Research's open-weight Hermes 4 family (14B / 70B / 405B) — a steerable, neutrally-aligned reasoning model with a hybrid 'thinking' mode, strong function calling and structured JSON output for agentic builders.
✅ Our verdict
Hermes 4 is the model for builders who want maximum control and neutral alignment, with first-class function calling and JSON output. It rewards teams comfortable adding their own guardrails in exchange for a highly steerable open model.
👍 Pros
- +Highly steerable, neutrally aligned
- +Hybrid reasoning (think vs. answer)
- +Excellent function calling & JSON mode
- +Three sizes incl. 405B
- +Fully open weights
👎 Cons
- −Raw model — you handle safety/guardrails
- −Largest size is hardware-heavy
- −Not as polished as hosted assistants
- −Smaller mainstream ecosystem
🎯 Use cases
ℹ️ Key facts
Last updated: Jun 2026
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Try Hermes 4 Now
Nous Research's open-weight Hermes 4 family (14B / 70B / 405B) — a steerable, neutrally-aligned reasoning model with a hybrid 'thinking' mode, strong function calling and structured JSON output for agentic builders.
❓ Frequently Asked Questions
Is Hermes 4 free?
Yes — Hermes 4 offers a free plan (Open weights / API via providers) plus a paid tier for advanced features and higher usage limits. You can start for free and upgrade only if you need more.
What is Hermes 4 used for?
Hermes 4 is an AI writing tool. Nous Research's open-weight Hermes 4 family (14B / 70B / 405B) — a steerable, neutrally-aligned reasoning model with a hybrid 'thinking' mode, strong function calling and structured JSON output for agentic builders. It currently holds a 4.4/5 rating on Aiverse from real users.
Is Hermes 4 worth it in 2026?
Hermes 4 is a solid choice with a 4.4/5 rating on Aiverse — a reliable option in the writing category, though it's worth comparing alternatives below for your specific needs.