Price, context and performance head to head. Data current as of April 2026.
Cheaper
Qwen 3.5 Flash
Larger context
Qwen 3.5 Flash
Faster
Qwen 3.5 Flash
Higher quality
Sonar Reasoning Pro
| Feature | Qwen 3.5 Flash | Sonar Reasoning Pro |
|---|---|---|
| Provider | Qwen | Perplexity |
| Tier | Budget | Reasoning |
| Input per 1M tokens | $0.065 | $2 |
| Output per 1M tokens | $0.26 | $8 |
| Cached input per 1M | $0.007 | $0.2 |
| Context window | 1M | 128K |
| Speed | Fast | Slow |
| Vision (image input) | No | No |
| Function calling | Yes | No |
| Batch API | No | No |
Enter how many requests per day you send with an average prompt (1K input + 1K output) and compare the monthly cost of both models.
Qwen 3.5 Flash saves $29/mo vs Sonar Reasoning Pro
Want us to build it for you?
We integrate Qwen 3.5 Flash or Sonar Reasoning Pro into your product with caching, observability and continuous evaluation — typically 40-80% cheaper than the obvious first pick.
Other combinations developers frequently compare in 2026.
What people ask us when comparing GPT, Claude, Gemini and the rest.
A token is the unit an AI model processes: usually between half a word and a full word. Rule of thumb: 1,000 tokens ≈ 750 English words. A 20-word sentence is about 26 tokens; a 300-word email is around 400. Models charge for input tokens (your prompt) and output tokens (their answer) separately.
