GPT-6.1 Terra Pro vs GLM 5.3 FlashX Legal
Detailed technical comparison between GPT-6.1 Terra Pro (OpenAI) and GLM 5.3 FlashX Legal (Zhipu AI). Review live API token pricing, context window capabilities, time-to-first-token latency, and verified benchmark scores side-by-side.
Comparison Snapshot
GPT-6.1 Terra Pro
1,050,000 tokensTie
Equal CapabilityTie
Equal SpeedGLM 5.3 FlashX Legal
$0.37 / MTokGPT-6.1 Terra Pro
GPT-6.1 Terra Pro is the same underlying model as [GPT-6.1 Terra](https://openrouter.ai/openai/gpt-6.1-terra), served with `reasoning.mode` set to `pro` for higher-quality responses on complex tasks. **Cost note:** pro mode spends far more...
GLM 5.3 FlashX Legal
GLM-5.3-FlashX-Legal (GLM-Legal) is Z.ai's legal-domain variant of GLM-5.3-FlashX, a native multimodal model that accepts text, image, and video input and produces text. It adds legal-domain mid-training and post-training with reinforcement...
Technical Specifications
🏆 = Superior Spec| Specification | GPT-6.1 Terra Pro | GLM 5.3 FlashX Legal |
|---|---|---|
| Provider | OpenAI | Zhipu AI |
| Context Window | 1,050,000 tokens🏆 | 1,048,576 tokens |
| Agent Suitability | Not yet benchmarked | Not yet benchmarked |
| Time to First Token (TTFT) | No public TTFT data | No public TTFT data |
| Deployment Model | managed api | managed api |
| Production Stability | Not verified | Not verified |
| API Available | Yes | Yes |
| Released Date | 2026-10-26 | 2026-11-02 |
API Pricing Comparison
Input Price per Million Tokens
GPT-6.1 Terra Pro
$1.00
GLM 5.3 FlashX Legal
$0.37
Output Price per Million Tokens
GPT-6.1 Terra Pro
$5.00
GLM 5.3 FlashX Legal
$1.25
💡 Cost Ratio: GLM 5.3 FlashX Legal is 2.7x cheaper per input token than GPT-6.1 Terra Pro.
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Benchmark Performance Metrics
Standardized Scores (0–100%)Scores show verified raw accuracy percentages across standardized AI evaluation suites. Higher bars indicate superior performance in that domain.
GPT-6.1 Terra Pro Quirks & Gotchas
No developer gotchas reported.
GLM 5.3 FlashX Legal Quirks & Gotchas
No developer gotchas reported.
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