Kimi K3.1 Pro vs GPT-6 Astra

API pricing, benchmark indices and specs — updated 24 October 2026.

moonshotai · A · API-only
Input / 1M
$2.00
Output / 1M
$10.00
AA index
55.1
proprietary · 1M context
openai · B · API-only
Input / 1M
$10.00
Output / 1M
$50.00
AA index
52.7
proprietary · 1.0M context

Specification comparison

Differences are highlighted; identical values are muted.

Specification Kimi K3.1 Pro GPT-6 Astra
Deployment API-only (closed weights) API-only (closed weights)
Parameters n/a — API-only n/a — API-only
Architecture n/a — API-only n/a — API-only
Context length 1,048,576 1,050,000
Licence Proprietary Proprietary
Commercial use Per API terms Per API terms
Languages n/a — API-only n/a — API-only
Downloads 30d n/a — API-only n/a — API-only
Downloads all time n/a — API-only n/a — API-only
Quantizations on the Hub n/a — API-only n/a — API-only
Gated n/a — API-only n/a — API-only
First seen on the Hub n/a — API-only n/a — API-only
API input price / 1M tokens $2.00 $10.00
API output price / 1M tokens $10.00 $50.00
Est. cost per 1M input + 1M output tokens $12.00 $60.00
Cached input / 1M tokens $0.20 $1.00
AA Intelligence Index 55.1 52.7
AA Coding Index — 76.9
AA Agentic Index — 51
Max output tokens 943,718 128,000
API providers 1 3
Tool calling Yes Yes
Reasoning mode Yes Yes

API cost

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

Kimi K3.1 Pro $12.00
GPT-6 Astra $60.00

Kimi K3.1 Pro is 5.0× cheaper at list price.

Adjacent comparisons