tokevenGPTvsGemini
o3 vs Gemini 3.1 Pro Custom Tools
Side-by-side comparison of pricing, task quality, and projected cost at higher scale.
Pricing
Side-by-side pricing
o3
Mid-tierGemini 3.1 Pro Custom Tools
Mid-tierInput $/MTok
$2.00
$2.00
Output $/MTok
$8.00
$12.00
Cache discount
75% off
90% off
Context
200K
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
0
Code Review
0
vs
0
Summarization
0
vs
0
Q&A
0
vs
0
Extraction
0
vs
0
Reasoning
0
vs
0
Classification
0
vs
0
Creative Writing
0
vs
0
o3
Gemini 3.1 Pro Custom Tools
Guidance
When to use o3 vs Gemini 3.1 Pro Custom Tools
Choose o3 when...
- Similar performance; consider provider preference or ecosystem fit.
Choose Gemini 3.1 Pro Custom Tools when...
- -You need a larger context window (1,048.576K vs 200K)
- Similar performance; consider provider preference or ecosystem fit.
At scale
Cost at scale
Estimated cost assuming a seventy percent input and thirty percent output token split.
o3
Gemini 3.1 Pro Custom Tools
100K tokens
$0.38Cheaper
$0.50
1M tokens
$3.80Cheaper
$8.20
10M tokens
$38.00Cheaper
$82.00
FAQ
When should I use o3 instead of Gemini 3.1 Pro Custom Tools?
o3 and Gemini 3.1 Pro Custom Tools perform similarly across all tracked tasks. Pick based on pricing and provider preference.
Is Gemini 3.1 Pro Custom Tools cheaper than o3?
Both models have the same input pricing at $2.00/MTok. Compare output pricing: $8.00 vs $12.00/MTok.
What are the context window sizes for o3 and Gemini 3.1 Pro Custom Tools?
o3 has a 200K token context window. Gemini 3.1 Pro Custom Tools has a 1,048.576K token context window.
Go deeper on either model
Per-call cost calculators, provider lineups, and price history for both models on this page.
Other comparisons
How o3 and Gemini 3.1 Pro Custom Tools stack up against the rest of the field.
Track your real costs
Comparisons show estimated costs at list price. The dashboard reveals your real spend and savings.