GPT-5.1 Chat vs DeepSeek V3.1
Detailed technical comparison between GPT-5.1 Chat (OpenAI) and DeepSeek V3.1 (DeepSeek). Review live API token pricing, context window capabilities, time-to-first-token latency, and verified benchmark scores side-by-side.
Comparison Snapshot
DeepSeek V3.1
163,840 tokensTie
Equal CapabilityTie
Equal SpeedDeepSeek V3.1
$0.25 / MTokGPT-5.1 Chat
GPT-5.1 Chat (AKA Instant is the fast, lightweight member of the 5.1 family, optimized for low-latency chat while retaining strong general intelligence. It uses adaptive reasoning to selectively “think” on...
DeepSeek V3.1
DeepSeek-V3.1 is a large hybrid reasoning model (671B parameters, 37B active) that supports both thinking and non-thinking modes via prompt templates. It extends the DeepSeek-V3 base with a two-phase long-context...
Technical Specifications
🏆 = Superior Spec| Specification | GPT-5.1 Chat | DeepSeek V3.1 |
|---|---|---|
| Provider | OpenAI | DeepSeek |
| Context Window | 128,000 tokens | 163,840 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 | self hostable |
| Production Stability | Stable GA (est.) | Stable GA (est.) |
| API Available | Yes | Yes |
| Released Date | 2025-11-13 | 2025-08-21 |
API Pricing Comparison
Input Price per Million Tokens
GPT-5.1 Chat
$1.25
DeepSeek V3.1
$0.25
Output Price per Million Tokens
GPT-5.1 Chat
$10.00
DeepSeek V3.1
$0.95
💡 Cost Ratio: DeepSeek V3.1 is 5.0x cheaper per input token than GPT-5.1 Chat.
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Run side-by-side prompt benchmarks in our dynamic multi-model Sandbox. Compare execution speeds, latency metrics, and compute actual costs in real-time.
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-5.1 Chat Quirks & Gotchas
No developer gotchas reported.
DeepSeek V3.1 Quirks & Gotchas
No developer gotchas reported.
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