Gemini 3.8 Flash vs Gemini 4 Argon

$0.93 / task
Wins 0 of 5 benchmarks
$1.99 / task
Wins 4 of 5 benchmarks
Different efforts: medium · high · Compare all at high
Humanity's Last Exam Humanity's Last Exam: Very hard expert questions across many fields, written to stump today’s models
Gemini 3.8 Flash42.1
Gemini 4 Argon57.1
Terminal-Bench 4.0 Terminal-Bench 4.0 · source setting 2: Agents use a terminal to complete executable coding, system administration and research tasks in the 4.0 suite
Gemini 3.8 Flash19.7
Gemini 4 Argon57.1
AutomationBench-AA AutomationBench-AA: Agents orchestrate SaaS workflows through APIs; objectives receive credit only when the task has no guardrail violation
Gemini 3.8 Flash60.9
Gemini 4 Argon77.5
Arena Text · creative writing Arena Text · creative writing: Human pairwise preferences in the stated text vote pool
Gemini 3.8 Flash · high1,487
Gemini 4 Argon1,516
MMMU-Pro (vision) MMMU-Pro (vision): College-level questions that require understanding images: charts, diagrams, photos
Gemini 3.8 Flash84.2
Gemini 4 Argon—

Specs

SpecGemini 3.8 FlashGemini 4 Argon
Input, per 1M!$0.75!$2
Output, per 1M!$3.75!$10
Cost per task?$0.93$1.99
Speed, tok/s—84
Context1M1M
WeightsClosedClosed
ReleasedSep 2026Oct 2026
See images✓✓
Read PDFs✓✓
Hear audio✓✓
Watch video✓✓
Call tools✓✓
Force a tool callPartialPartial
Return strict JSON✓✓
Search the web✓✓
Run code✓✓
Use a computer??

What breaks when you switch

Gemini 3.8 Flash → Gemini 4 Argon
Synchronous output stops at 65,536›

With background false, output limits above 65,536 tokens return HTTP 400; stay at or below that limit.

Sampling parameters are ignored›

temperature, top_p and top_k are ignored; remove them from requests.

No explicit caching›

Explicit caching is unavailable; omit explicit cache requests.

Gemini 4 Argon → Gemini 3.8 Flash
Sampling parameters are ignored›

temperature, top_p and top_k are ignored now and will cause HTTP 400 in future generations; remove them from requests.

No minimal thinking level›

The minimal thinking level returns an error; avoid minimal.