Compare / head-to-head

Gemini 3 Flash PreviewvsGPT-5.1-Codex-Max

Gemini 3 Flash Preview and GPT-5.1-Codex-Max split their 2 shared benchmarks evenly. Gemini 3 Flash Preview has the larger context window (1.0M tokens).

Benchmarks from cited public sources; pricing from official pages; status from official provider feeds.

Shared benchmarks
1 – 1
even split
Cheaper per token
—
list price, input + output
Larger context
Gemini 3 Flash Preview
1.0M tokens
Providers
2 providers
Google · OpenAI
Gemini 3 Flash Preview
Google · released 2025-12-17
textvisionaudio
Context
1.0M
Max out
66K
Input /1M
—
Output /1M
—
Cached /1M
—
Scores
34 · 12 core
GPT-5.1-Codex-Max
OpenAI · released 2025-11-19
textvision
Context
400K
Max out
128K
Input /1M
$1.25 ↗
Output /1M
$10 ↗
Cached /1M
$0.125
Scores
3 · 1 core
Quality

Benchmark matrix

BenchmarkGemini 3 Flash PreviewGPT-5.1-Codex-MaxΔEdge
Reported by both · 2
SWE-bench Verified78% ↗77.9% ↗+0.1 ptGemini 3 Flash Preview
Terminal-Bench 2.047.6% ↗58.1% ↗-10.5 ptGPT-5.1-Codex-Max
Only Gemini 3 Flash Preview reports · 24
GPQA Diamond90.4% ↗not reported——
AIME 202595.2% ↗not reported——
Humanity's Last Exam (no tools)33.7% ↗not reported——
LMArena Elo1472.7 ↗not reported——
BALROG (BALROG)48.1% ↗not reported——
Chess Puzzles (Epoch AI run)40% ↗epoch runnot reported——
FrontierMath Tier 4 v2 (Epoch AI run)17.1% ↗epoch runnot reported——
FrontierMath Tiers 1-3 v2 (Epoch AI run)51.2% ↗epoch runnot reported——
GSO Opt@1 (GSO)7.8% ↗not reported——
LMArena Vision (LMArena)1272.9 ↗not reported——
LMArena WebDev (LMArena)1438.9 ↗not reported——
MMMU-Pro81.2% ↗not reported——
Mystery Game Puzzles (Epoch AI run)26% ↗epoch runnot reported——
OTIS Mock AIME 2024-2025 (Epoch AI run)95.6% ↗epoch runnot reported——
SAGE (Vals AI)51.8% ↗not reported——
SimpleBench (SimpleBench)61.1% ↗not reported——
SimpleQA Verified68.7% ↗not reported——
SWE-bench Verified (Epoch AI run)75.4% ↗epoch runnot reported——
tau2-bench Airline (Sierra)82.5% ↗not reported——
tau2-bench Banking Knowledge (Sierra)27.3% ↗not reported——
tau2-bench Retail (Sierra)76.8% ↗not reported——
tau2-bench Telecom (Sierra)91.2% ↗not reported——
Vending-Bench 2 (Andon Labs)3634.72 ↗not reported——
WeirdML (Håvard Tveit Ihle)61.6% ↗not reported——
Only GPT-5.1-Codex-Max reports · 1
SWE-Lancer IC SWEnot reported79.9% ↗——
Scores tagged "epoch" or "matharena" are independent runs, used only where the lab has not published its own; ⚠ marks rows MathArena flags as released after the competition. Higher is better on every row. Δ is Gemini 3 Flash Preview minus GPT-5.1-Codex-Max in the benchmark's own unit. "Not reported" means the lab has not published that figure; it is not a zero. ↗ opens the source.
Specs & pricing

Side by side

SpecGemini 3 Flash PreviewGPT-5.1-Codex-MaxEdge
Context window1.0M tokens400K tokensGemini 3 Flash Preview
Max output66K tokens128K tokensGPT-5.1-Codex-Max
Input price / 1M—$1.25 ↗—
Output price / 1M—$10 ↗—
Cached input / 1M—$0.125 ↗—
Input + output / 1M
Lower is cheaper. List prices; batch, tool and regional fees excluded.
—$11.25—
Modalitiestext · vision · audiotext · visionGemini 3 Flash Preview
Released2025-12-172025-11-19—
Cited benchmark scores343—
Reliability

Provider status

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