ANTHROPIC VS XAI
Claude Fable 5 vs Grok 4.3
Grok 4.3 is about 13x cheaper than Claude Fable 5 on a blended 3:1 input:output rate — the same 10K-in/2K-out request costs $0.0175 vs $0.20. Both models have the same 1,000,000-token context window.
Pricing verified
API pricing per 1M tokens
| Model | Input / 1M tokens | Output / 1M tokens | Blended (3:1 mix) |
|---|---|---|---|
| Claude Fable 5 | $10.00 | $50.00 | $20.00 |
| Grok 4.3 | $1.25 | $2.50 | $1.563 |
Rates from official Anthropic pricing and official xAI pricing, checked 2026-08-11.
What a real workload costs
Example: one request with 10,000 input tokens and 2,000 output tokens, then that request at 100,000 runs per month.
| Model | Per request (10K in / 2K out) | Per month (100K requests) | Monthly delta |
|---|---|---|---|
| Claude Fable 5 | $0.20 | $20,000 | +$18,250 |
| Grok 4.3 | $0.0175 | $1,750 | — |
Model your own prompt sizes and volumes in the token cost analyzer, or check caching savings with the prompt caching calculator.
Specs side by side
| Spec | Claude Fable 5 | Grok 4.3 |
|---|---|---|
| Provider | Anthropic | xAI |
| Context window | 1,000,000 tokens | 1,000,000 tokens |
| Model class | Reasoning | Reasoning |
| Tokenizer | Proprietary (counts estimated) | Proprietary (counts estimated) |
Count tokens for each model on its own page: Claude Fable 5 token counter and Grok 4.3 token counter. All Anthropic models are on the Claude Token Counter. All xAI models are on the Grok Token Counter.
FAQ
Claude Fable 5 vs Grok 4.3 FAQ
Which is cheaper, Claude Fable 5 or Grok 4.3?
Grok 4.3 is cheaper. At rates checked 2026-08-11, Claude Fable 5 costs $10.00 input / $50.00 output per 1M tokens, while Grok 4.3 costs $1.25 input / $2.50 output — about a 13x difference on a typical 3:1 input-heavy workload.
How much does a real request cost on Claude Fable 5 vs Grok 4.3?
A request with 10,000 input tokens and 2,000 output tokens costs about $0.20 on Claude Fable 5 and $0.0175 on Grok 4.3. At 100,000 such requests per month that is $20,000 vs $1,750 — a difference of $18,250 per month.
Which has the bigger context window, Claude Fable 5 or Grok 4.3?
They are equal: both support 1,000,000 tokens of context, roughly 750,000 English words shared between prompt and response.
Do Claude Fable 5 and Grok 4.3 count tokens the same way?
Not exactly. Claude Fable 5 uses a proprietary tokenizer (counts are estimates) and Grok 4.3 uses a proprietary tokenizer (counts are estimates). The same prompt will tokenize differently, which shifts effective cost per word.