GPT-4.1 vs GPT-3.5 Turbo 16k

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

openai · A · API-only
Input / 1M
$2.00
Output / 1M
$8.00
AA index
12.7
proprietary · 1.0M context
openai · B · API-only
Input / 1M
$3.00
Output / 1M
$4.00
AA index
—
proprietary · 16.4K context

Specification comparison

Differences are highlighted; identical values are muted.

Specification GPT-4.1 GPT-3.5 Turbo 16k
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 1,047,576 16,385
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 $3.00
API output price / 1M tokens $8.00 $4.00
Est. cost per 1M input + 1M output tokens $10.00 $7.00
Cached input / 1M tokens $0.50 —
AA Intelligence Index 12.7 —
AA Coding Index — —
AA Agentic Index — —
Max output tokens 32,768 4,096
API providers 2 2
Tool calling Yes Yes
Reasoning mode No No

API cost

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

GPT-4.1 $10.00
GPT-3.5 Turbo 16k $7.00

GPT-3.5 Turbo 16k is 1.4× cheaper at list price.

Adjacent comparisons