Compare AI models

Specifications
Parameters
—21B
Context window
—128k
API pricing
Input price
$1.50—
Output price
$9.00—
Cached input price
$0.15—
Cheapest input
$0.75Google$0.018Darkbloom
Cheapest output
$4.50Google$0.09Darkbloom
Benchmarks
Humanity's Last Exam · no tools
40.2%10.9%
Humanity's Last Exam · with tools
40.2%17.3%
Overview
CompanyGoogleOpenAI
Release dateMay 19 2026Aug 5 2025
AccessClosedOpen Weight
Model detailsView modelView model

Frequently asked questions

Gemini 3.5 Flash leads gpt-oss-20b on 2 of the 2 benchmarks they both report (Humanity's Last Exam). Only Gemini 3.5 Flash has a verified first-party API price: $1.50 per million input tokens and $9.00 per million output tokens. No pay-as-you-go API rate is tracked for gpt-oss-20b. gpt-oss-20b shipped 287 days before Gemini 3.5 Flash, so benchmark comparisons should account for the intervening progress.

Gemini 3.5 Flash is closed, while gpt-oss-20b is open weight.

On Humanity's Last Exam · no tools, Gemini 3.5 Flash leads at 40.2% vs gpt-oss-20b at 10.9%. On Humanity's Last Exam · with tools, Gemini 3.5 Flash leads at 40.2% vs gpt-oss-20b at 17.3%.