DeepSeek V3.1 vs Qwen3.5 Plus 2026-04-20
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 DeepSeek V3.1 and Qwen3.5 Plus 2026-04-20.
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...
Qwen3.5 Plus 2026-04-20
Qwen3.5 Plus (April 2026) is a large-scale multimodal language model from Alibaba. It accepts text, image, and video input and produces text output, with a 1M token context window. This...
Technical Specifications
| Specification | DeepSeek V3.1 | Qwen3.5 Plus 2026-04-20 |
|---|---|---|
| Provider | DeepSeek | Alibaba |
| Context Window | 163,840 tokens | 1,000,000 tokens |
| Agent Suitability | N/A | N/A |
| Time to First Token (TTFT) | N/A | N/A |
| Deployment Model | self hostable | self hostable |
| Production Stability | stable | beta |
| API Available | Yes | Yes |
| Released Date | 2025-08-21 | 2026-04-27 |
API Pricing Comparison
Input Price per Million Tokens
DeepSeek V3.1
$0.21
Qwen3.5 Plus 2026-04-20
$0.30
Output Price per Million Tokens
DeepSeek V3.1
$0.79
Qwen3.5 Plus 2026-04-20
$1.80
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.
DeepSeek V3.1 Quirks & Gotchas
No developer gotchas reported.
Qwen3.5 Plus 2026-04-20 Quirks & Gotchas
No developer gotchas reported.