โ† Back to Model Hub/SIDE-BY-SIDE REVIEW
SHARE THIS:

Gemini 3.5 Flash vs gpt-oss-120b

How do these models stack up? Below is an expert side-by-side comparison of specifications, context window capacity, live pricing per million tokens, and standardized benchmark scores for Gemini 3.5 Flash and gpt-oss-120b.

Google

Gemini 3.5 Flash

Gemini 3.5 Flash is Google's high-efficiency multimodal model, bringing near-Pro level coding and reasoning at Flash-tier cost and speed. It is highly optimized for coding proficiency and parallel agentic execution...

View Full Specs
OpenAI

gpt-oss-120b

gpt-oss-120b is an open-weight, 117B-parameter Mixture-of-Experts (MoE) language model from OpenAI designed for high-reasoning, agentic, and general-purpose production use cases. It activates 5.1B parameters per forward pass and is optimized...

View Full Specs

Technical Specifications

SpecificationGemini 3.5 Flashgpt-oss-120b
ProviderGoogleOpenAI
Context Window1,048,576 tokens131,072 tokens
Agent Suitability88/100N/A
Time to First Token (TTFT)200 msN/A
Deployment Modelmanaged apimanaged api
Production Stabilitystablestable
API AvailableYesYes
Released Date2026-05-192025-08-05

API Pricing Comparison

Input Price per Million Tokens

Gemini 3.5 Flash

$1.50

gpt-oss-120b

$0.03

Output Price per Million Tokens

Gemini 3.5 Flash

$9.00

gpt-oss-120b

$0.15

Want to test both models live?

Run side-by-side prompt prompts in our dynamic Sandbox. Check execution speeds, latency metrics, and compute actual costs in real-time.

Benchmark Performance Metrics

Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.

MMLUGeneral knowledge & multi-task understanding
9050.0%vsN/A
Gemini 3.5 Flash
gpt-oss-120b
HumanEvalPython coding & logic synthesis
9210.0%vsN/A
Gemini 3.5 Flash
gpt-oss-120b
MATHComplex mathematical problem solving
8500.0%vsN/A
Gemini 3.5 Flash
gpt-oss-120b
GPQAGraduate-level expert reasoning
6820.0%vsN/A
Gemini 3.5 Flash
gpt-oss-120b
HellaSwagCommonsense reasoning and inference
9780.0%vsN/A
Gemini 3.5 Flash
gpt-oss-120b
MT-BenchMulti-turn conversation flow quality
920.0%vsN/A
Gemini 3.5 Flash
gpt-oss-120b

Gemini 3.5 Flash Quirks & Gotchas

  • โ–ธExcellent multimodal performance โ€” native video understanding
  • โ–ธTool calling via Google's native function_declarations in Vertex AI

gpt-oss-120b Quirks & Gotchas

No developer gotchas reported.