Gemini 3.8 Live Extended Thinking vs GPT-5.5 Pro
Pricing verdict: Gemini 3.8 Live Extended Thinking vs GPT-5.5 Pro: Gemini 3.8 Live Extended Thinking is cheaper for input-heavy usage ($0.75/M vs $30.00/M input tokens), while GPT-5.5 Pro is better for long-context tasks (1,050,000 tokens).
Direct answer: choose Gemini 3.8 Live Extended Thinking for lower token spend and choose GPT-5.5 Pro when your workload needs longer context.
Compare API pricing, input and output token costs, context windows, and monthly estimates on one page so you can pick the right model fast.
Cost Comparison (1000 input + 500 output tokens, 100 requests/day)
Gemini 3.8 Live Extended Thinking
GPT-5.5 Pro
Cost Differences
GPT-5.5 Pro costs more than Gemini 3.8 Live Extended Thinking
Quick Recommendation
Winner for direct API pricing: Gemini 3.8 Live Extended Thinking. At the default workload, Gemini 3.8 Live Extended Thinking saves about $351.00/month ($4,270.50/year) versus GPT-5.5 Pro.
Feature Comparison
| Feature | Gemini 3.8 Live Extended Thinking | GPT-5.5 Pro |
|---|---|---|
| Provider | OpenAI | |
| Input Price | $0.75/1M tokens | $30.00/1M tokens |
| Output Price | $4.50/1M tokens | $180.00/1M tokens |
| Context Window | 131,072 tokens | 1,050,000 tokens |
| Max Output | 65,536 tokens | 128,000 tokens |
| Category | reasoning | reasoning |
| Capabilities | textvisionaudiovideoreasoningstreaming | textvisioncodereasoning |
| Release Date | 9/15/2026 | 4/24/2026 |
Gemini 3.8 Live Extended Thinking vs GPT-5.5 Pro: Which Should You Choose?
Choosing between Gemini 3.8 Live Extended Thinking and GPT-5.5 Pro depends on your priorities: cost efficiency, context length, or raw capability. Gemini 3.8 Live Extended Thinking is the more affordable option at $0.75/1M input tokens — 98% cheaper than GPT-5.5 Pro. Meanwhile, GPT-5.5 Pro offers a significantly larger context window at 1,050,000 tokens vs 131,072 for Gemini 3.8 Live Extended Thinking.
These models come from different providers — Google and OpenAI — which means different API ecosystems, SDKs, rate limits, and terms of service. If you're already integrated with Google, switching to OpenAIinvolves migration effort beyond just pricing. Factor in your existing infrastructure when deciding.
Both models are in the reasoning category, making this a direct head-to-head comparison. At scale — say 10,000 requests per day — the cost difference adds up: Gemini 3.8 Live Extended Thinking would save you roughly $35,100.00/month compared to GPT-5.5 Pro. For startups and indie developers, that difference can be significant.
Output costs matter too. Gemini 3.8 Live Extended Thinking charges $4.50/1M output tokens vs $180.00 for GPT-5.5 Pro. For generation-heavy workloads (content creation, code generation, summarization), output pricing often dominates your bill. Gemini 3.8 Live Extended Thinking has the edge here at $4.50/1M output tokens.
Multimodal capabilities: Both models support vision (image understanding), so you can send images alongside text prompts with either option.
Best Use Cases
Choose Gemini 3.8 Live Extended Thinking when:
- • Budget is a primary concern
- • You need more capabilities (audio, video, streaming)
- • You're already using Google's API ecosystem
Choose GPT-5.5 Pro when:
- • You need a larger context window (1,050,000 tokens)
- • You need longer outputs (up to 128,000 tokens)
- • You're already using OpenAI's API ecosystem
Pros and Caveats at a Glance
Gemini 3.8 Live Extended Thinking
- • Input pricing: $0.75/M tokens
- • Output pricing: $4.50/M tokens
- • Context window: 131,072 tokens
- • Max output: 65,536 tokens
Watch out for
- • Smaller context window than GPT-5.5 Pro
GPT-5.5 Pro
- • Input pricing: $30.00/M tokens
- • Output pricing: $180.00/M tokens
- • Context window: 1,050,000 tokens
- • Max output: 128,000 tokens
Watch out for
- • Higher input cost than Gemini 3.8 Live Extended Thinking
- • Higher output cost than Gemini 3.8 Live Extended Thinking
Try Different Scenarios
Use the calculator below to see how costs change with different usage patterns
Gemini 3.8 Live Extended Thinking (Google)
GPT-5.5 Pro (OpenAI)
Start using Gemini 3.8 Live Extended Thinking today
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Sign Up for OpenAI →Frequently Asked Questions
Which is cheaper, Gemini 3.8 Live Extended Thinking or GPT-5.5 Pro?▼
What is the context window difference between Gemini 3.8 Live Extended Thinking and GPT-5.5 Pro?▼
Which model is better for AI Chatbot?▼
Which model has better overall pricing for heavy usage?▼
Where can I compare Google and OpenAI API pricing beyond this model matchup?▼
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