GPT-5.5 Pro vs Yi-Lightning
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 GPT-5.5 Pro and Yi-Lightning.
GPT-5.5 Pro
GPT-5.5 Pro is OpenAI’s high-capability model optimized for deep reasoning and accuracy on complex, high-stakes workloads. It features a 1M+ token context window (922K input, 128K output) with support for...
Yi-Lightning
Yi-Lightning is 01.AI's (零一万物) fastest and most cost-efficient model, purpose-built for high-throughput production workloads. It delivers competitive performance against GPT-4o-mini and Claude Haiku at a fraction of the cost, with exceptional bilingual Chinese-English capabilities. Yi-Lightning excels at classification, entity extraction, summarization, and high-frequency API tasks where latency and cost-per-call are critical constraints.
Technical Specifications
| Specification | GPT-5.5 Pro | Yi-Lightning |
|---|---|---|
| Provider | OpenAI | 01.AI |
| Context Window | 1,050,000 tokens | 131,072 tokens |
| Agent Suitability | 98/100 | 82/100 |
| Time to First Token (TTFT) | 450 ms | 120 ms |
| Deployment Model | managed api | managed api |
| Production Stability | beta | stable |
| API Available | Yes | Yes |
| Released Date | 2026-04-24 | 2025-10-01 |
API Pricing Comparison
Input Price per Million Tokens
GPT-5.5 Pro
$30.00
Yi-Lightning
$0.15
Output Price per Million Tokens
GPT-5.5 Pro
$180.00
Yi-Lightning
$0.30
Want to test both models live?
Run side-by-side prompt prompts in our dynamic Sandbox. Check execution speeds, latency metrics, and compute actual costs in real-time.
Benchmark Performance Metrics
Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.
GPT-5.5 Pro Quirks & Gotchas
- ▸Best-in-class instruction following for complex agentic chains
- ▸Premium pricing — use GPT-5 for cost-sensitive workloads
Yi-Lightning Quirks & Gotchas
- ▸Best cost-efficiency for high-volume bilingual applications
- ▸Self-hostable via Ollama — excellent open-weight option for Asian-language pipelines