Compare Claude Opus 5 from Anthropic and Gemini 3.8 Flash from Google on key metrics including benchmarks, price, context length, and other model features. Access both models and hundreds of others through the OpenRouter API.
Claude Opus 5 and Gemini 3.8 Flash are available through the OpenRouter API, so switching between them takes a model slug change rather than a new integration.
Claude Opus 5, from Anthropic, has a 1,000,000-token context window and is priced at $5/M tokens input, $25/M tokens output on OpenRouter.
Gemini 3.8 Flash, from Google, has a 1,048,576-token context window and is priced at $0.75/M tokens input, $3.75/M tokens output on OpenRouter.
| Claude Opus 5 | Gemini 3.8 Flash | |
|---|---|---|
| Input price | $5/M tokens | $0.75/M tokens |
| Output price | $25/M tokens | $3.75/M tokens |
| Context window | 1,000,000 tokens | 1,048,576 tokens |
| Intelligence Index | 50.8 | 40.9 |
| Coding Index | 78.0 | 76.3 |
| Agentic Index | 56.5 | 40.2 |
| Latency (p50) | 2.80 s | 1.54 s |
| Throughput (p50) | 68.0 tok/s | 148.0 tok/s |
Gemini 3.8 Flash is cheaper than Claude Opus 5 on OpenRouter: Gemini 3.8 Flash costs $0.75/M tokens input and $3.75/M tokens output, while Claude Opus 5 costs $5/M tokens input and $25/M tokens output.
Gemini 3.8 Flash has the longer context window at 1,048,576 tokens, compared with 1,000,000 tokens for Claude Opus 5.
Gemini 3.8 Flash is faster on OpenRouter, generating a median 148.0 tokens per second compared with 68.0 tokens per second for Claude Opus 5.
Claude Opus 5 scores higher on coding, with an Artificial Analysis Coding Index of 78.0 compared with 76.3 for Gemini 3.8 Flash.