GPT-5 Nano vs Gemini 2.5 Flash Lite

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

openai · A · API-only
Input / 1M
$0.05
Output / 1M
$0.40
AA index
13
proprietary · 400K context
google · B · API-only
Input / 1M
$0.10
Output / 1M
$0.40
AA index
10.4
proprietary · 1M context

Specification comparison

Differences are highlighted; identical values are muted.

Specification GPT-5 Nano Gemini 2.5 Flash Lite
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 400,000 1,048,576
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 $0.05 $0.10
API output price / 1M tokens $0.40 $0.40
Est. cost per 1M input + 1M output tokens $0.45 $0.50
Cached input / 1M tokens $0.005 $0.01
AA Intelligence Index 13 10.4
AA Coding Index — —
AA Agentic Index — —
Max output tokens 128,000 65,535
API providers 2 1
Tool calling Yes Yes
Reasoning mode Yes Yes

API cost

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

GPT-5 Nano $0.45
Gemini 2.5 Flash Lite $0.50

GPT-5 Nano is 1.1× cheaper at list price.

Adjacent comparisons