Hermes-4-405B vs Solar Pro 3

API pricing, benchmark indices and specs — updated 19 October 2026.

NousResearch · A · Open weights
Params
405.9 B
Context
131,072
30d
1 K
llama3 licence · conditional
upstage · B · API-only
Input / 1M
$0.15
Output / 1M
$0.60
AA index
7.8
proprietary · 131.1K context

Specification comparison

Differences are highlighted; identical values are muted.

Specification Hermes-4-405B Solar Pro 3
Deployment Open weights · also via API API-only (closed weights)
Parameters 405.9 B n/a — API-only
Architecture LlamaForCausalLM n/a — API-only
Context length 131,072 131,072
Licence llama3 Proprietary
Commercial use Conditional Per API terms
Languages 1 n/a — API-only
Downloads 30d 1,216 n/a — API-only
Downloads all time 8 K n/a — API-only
Quantizations on the Hub SAFETENSORS n/a — API-only
Gated No n/a — API-only
First seen on the Hub 2025-08-06 n/a — API-only
API input price / 1M tokens $1.00 $0.15
API output price / 1M tokens $3.00 $0.60
Est. cost per 1M input + 1M output tokens $4.00 $0.75
Cached input / 1M tokens — $0.015
AA Intelligence Index 7.5 7.8
AA Coding Index — 16.2
AA Agentic Index — 1.4
Max output tokens 117,964 117,964
API providers 1 1
Tool calling No Yes
Reasoning mode Yes Yes

API cost

Estimated cost of 1M input + 1M output tokens via OpenRouter

Hermes-4-405B $4.00
Solar Pro 3 $0.75

Solar Pro 3 is 5.3× cheaper at list price.

VRAM side by side

On RTX 4090 · 24 GB · 8K context unless noted

Hermes-4-405B · fp16 @ 128K ctx 1,867.4 GB / 24 GB
❌ Won’t fit

Adjacent comparisons