Gemini 3.1 Flash Lite Preview vs GPT-5 Nano

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

google · A · API-only
Input / 1M
$0.25
Output / 1M
$1.50
AA index
15.6
proprietary · 1M context
openai · B · API-only
Input / 1M
$0.05
Output / 1M
$0.40
AA index
13
proprietary · 400K context

Specification comparison

Differences are highlighted; identical values are muted.

Specification Gemini 3.1 Flash Lite Preview GPT-5 Nano
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 1,048,576 400,000
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 $0.25 $0.05
API output price / 1M tokens $1.50 $0.40
Est. cost per 1M input + 1M output tokens $1.75 $0.45
Cached input / 1M tokens $0.025 $0.005
AA Intelligence Index 15.6 13
AA Coding Index 34.7 —
AA Agentic Index 1.6 —
Max output tokens 65,536 128,000
API providers 1 2
Tool calling Yes Yes
Reasoning mode Yes Yes

API cost

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

Gemini 3.1 Flash Lite Preview $1.75
GPT-5 Nano $0.45

GPT-5 Nano is 3.9× cheaper at list price.

Adjacent comparisons