GPTvsGemini

GPT 5.1 vs Gemini 3 Flash

Side-by-side comparison of pricing, task quality, and projected cost at higher scale.

Pricing

Side-by-side pricing

GPT 5.1

Mid-tier

Gemini 3 Flash

Fast / Budget
Input $/MTok
$1.25
$0.50
Output $/MTok
$10.00
$3.00
Cache discount
90% off
90% off
Context
272K
1,048.576K

Quality

Task confidence comparison

Confidence score from zero to one hundred by task type, where higher is better.
Code Generation
0
vs
65
Code Review
0
vs
62
Summarization
0
vs
83
Q&A
0
vs
82
Extraction
0
vs
86
Reasoning
0
vs
58
Classification
0
vs
88
Creative Writing
0
vs
52
GPT 5.1
Gemini 3 Flash

Guidance

When to use GPT 5.1 vs Gemini 3 Flash

Choose GPT 5.1 when...

  • Similar performance; consider provider preference or ecosystem fit.

Choose Gemini 3 Flash when...

  • -Cost matters: 60% cheaper on input tokens
  • -You need a larger context window (1,048.576K vs 272K)

At scale

Cost at scale

Estimated cost assuming a seventy percent input and thirty percent output token split.
GPT 5.1
Gemini 3 Flash
100K tokens
$0.39
$0.13Cheaper
1M tokens
$3.88
$1.25Cheaper
10M tokens
$38.75
$12.50Cheaper

FAQ

When should I use GPT 5.1 instead of Gemini 3 Flash?

GPT 5.1 and Gemini 3 Flash perform similarly across all tracked tasks. Pick based on pricing and provider preference.

Is Gemini 3 Flash cheaper than GPT 5.1?

Yes. Gemini 3 Flash input costs $0.50/MTok vs $1.25/MTok for GPT 5.1, saving 60% on input.

What are the context window sizes for GPT 5.1 and Gemini 3 Flash?

GPT 5.1 has a 272K token context window. Gemini 3 Flash has a 1,048.576K token context window.

Track your real costs

Comparisons show estimated costs at list price. The dashboard reveals your real spend and savings.