ANTHROPIC VS XAI
Claude Opus 4.8 vs Grok 4.3
Grok 4.3 is about 6.4x cheaper than Claude Opus 4.8 on a blended 3:1 input:output rate — the same 10K-in/2K-out request costs $0.0175 vs $0.10. 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 Opus 4.8 | $5.00 | $25.00 | $10.00 |
| 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 Opus 4.8 | $0.10 | $10,000 | +$8,250 |
| 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 Opus 4.8 | 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 Opus 4.8 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 Opus 4.8 vs Grok 4.3 FAQ
Which is cheaper, Claude Opus 4.8 or Grok 4.3?
Grok 4.3 is cheaper. At rates checked 2026-08-11, Claude Opus 4.8 costs $5.00 input / $25.00 output per 1M tokens, while Grok 4.3 costs $1.25 input / $2.50 output — about a 6.4x difference on a typical 3:1 input-heavy workload.
How much does a real request cost on Claude Opus 4.8 vs Grok 4.3?
A request with 10,000 input tokens and 2,000 output tokens costs about $0.10 on Claude Opus 4.8 and $0.0175 on Grok 4.3. At 100,000 such requests per month that is $10,000 vs $1,750 — a difference of $8,250 per month.
Which has the bigger context window, Claude Opus 4.8 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 Opus 4.8 and Grok 4.3 count tokens the same way?
Not exactly. Claude Opus 4.8 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.