Model comparison
Claude Fable 5.1 vs Grok 4.7
Claude Fable 5.1 (Anthropic) and Grok 4.7 (xAI) side by side: what each costs per million tokens through Rapid Router, how much context each takes, what each supports, and where independent benchmarks place them. Same API, same key; switching is a one-string change.
| Claude Fable 5.1 | Grok 4.7 | |
|---|---|---|
| Input price per 1M | $10.00 | $2.00 |
| Output price per 1M | $50.00 | $6.00 |
| Context window | 1M tokens | 500K tokens |
| Max output | 128K tokens | 500K tokens |
| Input types | text, image, pdf | text, image, pdf |
| Capabilities | tools, JSON, vision, reasoning | tools, JSON, vision, reasoning |
| Author | Anthropic | xAI |
What a month costs on each
| Workload | Claude Fable 5.1 | Grok 4.7 |
|---|---|---|
| Chatbot month (15M in, 4M out) | $350.00 | $54.00 |
| RAG month (40M in, 3M out) | $550.00 | $98.00 |
| Coding month (60M in, 10M out) | $1100.00 | $180.00 |
On a typical 75/25 input-output mix, Grok 4.7 costs less (about 85% less than Claude Fable 5.1). Claude Fable 5.1 takes the longer prompt at 1M tokens. Try your own numbers in the cost calculator.
Call either one
curl https://rapidrouter.ai/api/v1/chat/completions \
-H "Authorization: Bearer $RAPIDROUTER_API_KEY" \
-H "Content-Type: application/json" \
-d '{"model": "anthropic/claude-fable-5-1", "messages": [{"role": "user", "content": "Hello"}]}'
# the other one: change the model string
-d '{"model": "x-ai/grok-4.7", ...}'Common questions
Which is cheaper, Claude Fable 5.1 or Grok 4.7?
Grok 4.7 is cheaper on a typical mix of 75% input and 25% output tokens, by about 85%. Through Rapid Router both are billed at the provider list price per million tokens.
Which has the larger context window?
Claude Fable 5.1, at 1M tokens. Grok 4.7 offers 500K tokens.
Can I switch between Claude Fable 5.1 and Grok 4.7 without changing code?
Yes. Both are callable at https://rapidrouter.ai/api/v1 with the same OpenAI-compatible request; only the model string changes (anthropic/claude-fable-5-1 or x-ai/grok-4.7).
How do I pay for Claude Fable 5.1 or Grok 4.7?
Top up a Rapid Router balance by card in US dollars, and both models debit that balance per request.
More Claude models: Anthropic API pricing · More Grok: xAI API pricing