Gemini 2.5 Flash vs GPT-5.3 Chat
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 2.5 Flash and GPT-5.3 Chat.
Gemini 2.5 Flash
Gemini 2.5 Flash is Google's state-of-the-art workhorse model, specifically designed for advanced reasoning, coding, mathematics, and scientific tasks. It includes built-in "thinking" capabilities, enabling it to provide responses with greater...
GPT-5.3 Chat
GPT-5.3 Chat is an update to ChatGPT's most-used model that makes everyday conversations smoother, more useful, and more directly helpful. It delivers more accurate answers with better contextualization and significantly...
Technical Specifications
| Specification | Gemini 2.5 Flash | GPT-5.3 Chat |
|---|---|---|
| Provider | OpenAI | |
| Context Window | 1,048,576 tokens | 128,000 tokens |
| Agent Suitability | N/A | N/A |
| Time to First Token (TTFT) | N/A | N/A |
| Deployment Model | managed api | managed api |
| Production Stability | beta | stable |
| API Available | Yes | Yes |
| Released Date | 2025-06-17 | 2026-03-03 |
API Pricing Comparison
Input Price per Million Tokens
Gemini 2.5 Flash
$0.30
GPT-5.3 Chat
$1.75
Output Price per Million Tokens
Gemini 2.5 Flash
$2.50
GPT-5.3 Chat
$14.00
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Benchmark Performance Metrics
Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.
Gemini 2.5 Flash Quirks & Gotchas
No developer gotchas reported.
GPT-5.3 Chat Quirks & Gotchas
No developer gotchas reported.