context window size - chunhualiao/public-docs GitHub Wiki
The input context window sizes for popular AI models from OpenAI, Anthropic (Claude), xAI (Grok), and Google (Gemini) as of May 2025 are summarized below, based on available web and X post data. Note that context window sizes refer to the maximum number of tokens (input and output combined) a model can process in a single interaction. For C++ coding, larger context windows are particularly useful for handling large codebases, as they allow the model to consider entire files or projects at once.
| Model | Context Window Size (Tokens) | Source |
|---|---|---|
| OpenAI GPT-4o | 128,000 | |
| OpenAI o3 | 200,000 | |
| OpenAI o3-mini | 200,000 | |
| Claude 3.7 Sonnet | 200,000 | |
| Claude 3.5 Sonnet | 200,000 (500,000 for Claude Enterprise) | |
| Grok 3 | 1,000,000 | |
| Grok 3 Mini | Not explicitly stated (assumed ~1,000,000, same as Grok 3) | |
| Gemini 2.5 Pro | 1,000,000 (2,000,000 via API) | |
| Gemini 2.5 Flash | 1,000,000 | |
| Gemini 1.5 Pro | 2,000,000 |
Notes:
- OpenAI: GPT-4o has a 128,000-token context window, while the newer o3 and o3-mini models offer 200,000 tokens, making them suitable for larger C++ projects.
- Claude: Both Claude 3.7 Sonnet and Claude 3.5 Sonnet provide 200,000 tokens, with an expanded 500,000-token option for Claude Enterprise users, ideal for enterprise-scale C++ codebases.
- Grok: Grok 3 supports a 1,000,000-token context window, which is competitive for large coding projects, though exact details for Grok 3 Mini are not explicitly stated but assumed similar.
- Gemini: Gemini 2.5 Pro and Flash offer 1,000,000 tokens, with Gemini 1.5 Pro reaching up to 2,000,000 tokens, the largest among commercial models, making it exceptionally suited for massive C++ codebases.
- Token Estimation for C++: As noted in my previous response, C++ code typically yields ~1 token per 3–5 characters or ~5–10 tokens per line. For example, a 30,000-character C++ file is ~6,000–10,000 tokens, and a 30,000-line codebase could be ~150,000–300,000 tokens. Thus, Gemini 1.5 Pro and Grok 3 can handle significantly larger codebases than Claude or GPT-4o.
- Caveats: Some X posts suggest effective context windows (where models maintain high-quality recall) may be lower than advertised (e.g., ~32,000–256,000 tokens for Claude and GPT models), but this is not conclusive. Always verify with official documentation or APIs for precise limits, as platforms like grok.com or x.ai/api may provide updated details.
For the most accurate and up-to-date information, check official sources like https://x.ai/grok for Grok, https://x.ai/api for xAI’s API, or respective documentation for OpenAI, Anthropic, and Google. If you have a specific C++ project, I can help estimate its token count to ensure it fits within these context windows!