tokevenGPTvsGemini
GPT 5.5 Pro vs Gemini 3.8 Flash
Side-by-side comparison of pricing, task quality, and projected cost at higher scale.
Pricing
Side-by-side pricing
GPT 5.5 Pro
FlagshipGemini 3.8 Flash
Fast / BudgetInput $/MTok
$30.00
$0.75
Output $/MTok
$180.00
$3.75
Cache discount
0% off
90% off
Context
1,050K
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
GPT 5.5 Pro
Gemini 3.8 Flash
Guidance
When to use GPT 5.5 Pro vs Gemini 3.8 Flash
Choose GPT 5.5 Pro when...
- -You need a larger context window (1,050K vs 1,048.576K)
- Similar performance; consider provider preference or ecosystem fit.
Choose Gemini 3.8 Flash when...
- -Cost matters: 98% cheaper on input tokens
At scale
Cost at scale
Estimated cost assuming a seventy percent input and thirty percent output token split.
GPT 5.5 Pro
Gemini 3.8 Flash
100K tokens
$7.50
$0.16Cheaper
1M tokens
$123.00
$1.65Cheaper
10M tokens
$1230.00
$16.50Cheaper
FAQ
When should I use GPT 5.5 Pro instead of Gemini 3.8 Flash?
GPT 5.5 Pro and Gemini 3.8 Flash perform similarly across all tracked tasks. Pick based on pricing and provider preference.
Is Gemini 3.8 Flash cheaper than GPT 5.5 Pro?
Yes. Gemini 3.8 Flash input costs $0.75/MTok vs $30.00/MTok for GPT 5.5 Pro, saving 98% on input.
What are the context window sizes for GPT 5.5 Pro and Gemini 3.8 Flash?
GPT 5.5 Pro has a 1,050K token context window. Gemini 3.8 Flash 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 GPT 5.5 Pro and Gemini 3.8 Flash 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.