AI Model Release Tracker - Timeline of Major AI Models from 2022-2026

Gemini 3.5 Flash vs o4-mini

Google
Gemini 3.5 Flash
OpenAI
o4-mini
Overview
CompanyGoogleOpenAI
Release dateMay 19 2026Apr 16 2025
AccessProprietaryProprietary
Benchmarks
Nonsense detection
BullshitBench v2
20%Best
8%
Agentic coding
SWE-Bench Pro
55.1%
Agentic coding
CursorBench v3.1
49.8%
Agentic terminal coding
Terminal-Bench 2.1
76.2%
Multi-step tool use
MCP Atlas
83.6%
General tool use
Toolathlon
56.5%
Multidisciplinary reasoning
Humanity's Last Exam · no tools
40.2%
Abstract reasoning
ARC-AGI-2
72.1%
Agentic computer use
OSWorld-Verified
78.4%
Agentic financial analysis
Finance Agent v2
57.9%
Knowledge work
GDPval-AA
1656
Chart reasoning
CharXiv Reasoning
84.2%
Multimodal reasoning
MMMU-Pro
83.6%
Spatial reasoning
Blueprint-Bench 2
33.6%
Long context
MRCR v2 (8-needle) · 128k average
77.3%
Long context
MRCR v2 (8-needle) · 1M pointwise
26.6%
Timeline
Release gapo4-mini shipped 398 days before Gemini 3.5 Flash

Which is better: Gemini 3.5 Flash or o4-mini?

Gemini 3.5 Flash leads o4-mini on 1 of the 1 benchmark they both report (BullshitBench v2). o4-mini shipped 398 days before Gemini 3.5 Flash, so benchmark comparisons should account for the intervening progress.

Published specifications for these two models are limited — see each model page for the latest details.

On BullshitBench v2, Gemini 3.5 Flash leads at 20% vs o4-mini at 8%.

Frequently asked questions

Gemini 3.5 Flash was released by Google on May 19 2026.

o4-mini was released by OpenAI on Apr 16 2025.

Other comparisons