Seed 1.6 is $0.05 cheaper per 1M input tokens (16.7% lower; 1.2x difference).
API cost decision in 10 seconds
Qwen3.5 Plus 2026-04-20 vs Seed 1.6
Pick Qwen3.5 Plus 2026-04-20 when budget and context both matter.
Page updated:
Data confirmed:
Prices normalized to USD per 1M tokens
Sample workload: 1M input + 500K output
Budget verdict
Pick Qwen3.5 Plus 2026-04-20 when budget and context both matter.
On the standard 1M input plus 500K output workload, Qwen3.5 Plus 2026-04-20 is estimated at $1.2 vs $1.25 for Seed 1.6, saving $0.05 (4% lower).
Cost-first pickQwen3.5 Plus 2026-04-20
Context-first pickQwen3.5 Plus 2026-04-20
Sample savings$0.054%
10x traffic gap$0.5
Qwen3.5 Plus 2026-04-20 is cheaper on the standard workload and also has the larger context window. At 10x that traffic, the same price gap is about $0.5. Use the calculator below to replace the sample workload with your own token volume.
Cost sensitivity
Workload Sensitivity
Cost winner changes by workload shape: input-heavy / RAG favors Seed 1.6, balanced workload favors Qwen3.5 Plus 2026-04-20, and output-heavy chatbot favors Qwen3.5 Plus 2026-04-20.
| Workload shape | Token mix | Better pick | Qwen3.5 Plus 2026-04-20 | Seed 1.6 |
|---|---|---|---|---|
| Input-heavy / RAG | 5M input + 500K output | Seed 1.6 | $2.4 | $2.25 |
| Balanced workload | 1M input + 1M output | Qwen3.5 Plus 2026-04-20 | $2.1 | $2.25 |
| Output-heavy chatbot | 1M input + 5M output | Qwen3.5 Plus 2026-04-20 | $9.3 | $10.25 |
Qwen3.5 Plus 2026-04-20 is $0.2 cheaper per 1M output tokens (10% lower; 1.11x difference).
Qwen3.5 Plus 2026-04-20 has 737.86K more context (3.81x larger).
Qwen3.5 Plus 2026-04-20 is $0.05 cheaper on the standard workload (4% lower).
Estimate your workload cost
Your Workload Cost
This estimate uses normalized public API pricing per 1M tokens. It is a planning aid, not a billing quote. Verify provider pricing, limits, and terms before production use.
Quick Decision
Seed 1.6 has the lower input price; Qwen3.5 Plus 2026-04-20 has the lower output price; Qwen3.5 Plus 2026-04-20 offers the larger context window. For the 1M input plus 500K output sample, Qwen3.5 Plus 2026-04-20 is cheaper for the standard workload.
For a 1M input token plus 500K output token workload, the estimated API cost is $1.2 for Qwen3.5 Plus 2026-04-20 and $1.25 for Seed 1.6.
Choose Qwen3.5 Plus 2026-04-20 when you care most about lower output-token price, and larger context window.
Choose Seed 1.6 when you care most about lower input-token price.
- On the standard 1M input plus 500K output workload, Qwen3.5 Plus 2026-04-20 is estimated at $1.2 vs $1.25 for Seed 1.6, saving $0.05 (4% lower).
- Qwen3.5 Plus 2026-04-20 is $0.05 cheaper on the standard workload (4% lower).
- Seed 1.6 is $0.05 cheaper per 1M input tokens (16.7% lower; 1.2x difference).
- Qwen3.5 Plus 2026-04-20 is $0.2 cheaper per 1M output tokens (10% lower; 1.11x difference).
- Qwen3.5 Plus 2026-04-20 has 737.86K more context (3.81x larger).
| Feature | Qwen3.5 Plus 2026-04-20 (Qwen) | Seed 1.6 (ByteDance Seed) |
|---|---|---|
| Input Price prompt tokens per 1M | $0.3 | $0.25 |
| Completion Price per 1M tokens | $1.8 | $2 |
| Sample Workload Cost 1M input + 500K output | $1.2 | $1.25 |
| Context Window | 1M | 262.14K |
| Release Date |
Use-Case Decision Matrix
| Use case | Better pick | Why |
|---|---|---|
| Budget-constrained production | Qwen3.5 Plus 2026-04-20 | On the standard 1M input plus 500K output workload, Qwen3.5 Plus 2026-04-20 is estimated at $1.2 vs $1.25 for Seed 1.6, saving $0.05 (4% lower). |
| High-volume input processing | Seed 1.6 | Lower prompt-token price matters most when prompts, retrieved passages, or documents dominate the bill. |
| Long responses and chatbots | Qwen3.5 Plus 2026-04-20 | Lower output-token price matters most when assistants generate many completion tokens. |
| RAG or long-document work | Qwen3.5 Plus 2026-04-20 | A larger context window leaves more room for retrieved passages, conversation history, or source files. |
Related Alternatives
- Qwen3 Next 80B A3B Instruct (free) can replace Qwen3.5 Plus 2026-04-20 when lower sample workload cost matters most: $0.
- Qwen3 Coder 480B A35B (free) can replace Qwen3.5 Plus 2026-04-20 when lower sample workload cost matters most: $0.
- Qwen2.5 7B Instruct can replace Qwen3.5 Plus 2026-04-20 when lower sample workload cost matters most: $0.09.
- Qwen3.5-9B can replace Qwen3.5 Plus 2026-04-20 when lower sample workload cost matters most: $0.11.
- Llama 4 Scout offers 10M context with $0.23 sample workload cost.
- Owl Alpha offers 1.05M context with $0 sample workload cost.
- DeepSeek V4 Flash offers 1.05M context with $0.2 sample workload cost.
- DeepSeek V4 Pro offers 1.05M context with $0.87 sample workload cost.
- DeepSeek V4 Flash · DeepSeek · #1
- Hy3 preview · Tencent · #2
- Claude Opus 4.7 · Anthropic · #3
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Open ByteDance Seed modelsQwen3.5 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...
Seed 1.6 is a general-purpose model released by the ByteDance Seed team. It incorporates multimodal capabilities and adaptive deep thinking with a 256K context window.