Price, context and performance head to head. Data current as of April 2026.
Cheaper
Grok 4.1 Fast
Larger context
Grok 4.1 Fast
Faster
Tied
Higher quality
Sonar
| Feature | Grok 4.1 Fast | Sonar |
|---|---|---|
| Provider | xAI | Perplexity |
| Tier | Budget | Mid-tier |
| Input per 1M tokens | $0.2 | $1 |
| Output per 1M tokens | $0.5 | $1 |
| Cached input per 1M | $0.05 | $0.1 |
| Context window | 2M | 127K |
| Speed | Fast | Fast |
| 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.
Grok 4.1 Fast saves $3.9/mo vs Sonar
Want us to build it for you?
We integrate Grok 4.1 Fast or Sonar 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.
