Grok 4.5 vs Grok 4.3: cost compared
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Grok 4.3 is 38% cheaper on input and 58% cheaper on output than Grok 4.5. Whether that makes it the right choice depends entirely on whether it does your task well enough — this page gives you the cost side of that trade, precisely.
Rates side by side
| $ per million tokens | Grok 4.5 | Grok 4.3 |
|---|---|---|
| Input | $2.00 | $1.25 |
| Output | $6.00 | $2.50 |
| Cached input | $0.30 | $0.20 |
| Output : input ratio | 3.0× | 2.0× |
What the difference is worth
Monthly cost for the same workload on each, without caching:
| Workload | Grok 4.5 | Grok 4.3 | Difference |
|---|---|---|---|
| Support chatbot 1,000 conversations/month · 2,000 in + 500 out each | $7.00 | $3.75 | $3.25 saved |
| RAG search 10,000 queries/month · 8,000 in + 400 out each | $184 | $110 | $74.00 saved |
| Bulk extraction 10,000 documents · 3,000 in + 300 out each | $78.00 | $45.00 | $33.00 saved |
| Coding agent 100 runs/month · 400,000 in + 20,000 out each | $92.00 | $55.00 | $37.00 saved |
Which to use
Grok 4.3 if the task is well-specified and mechanical — extraction, classification, formatting, routine transformation. The saving is real and compounds with volume.
Grok 4.5 if the task involves genuine reasoning, long-horizon planning, or work where a wrong answer is expensive to catch. Paying 1.6× more on input is trivial compared to the cost of shipping a bad result.
Both are xAI models, so switching is usually a one-line change and the tokenizer is the same — which makes this a genuinely easy experiment to run. Test on your own workload before deciding.
Don't skip caching
Cached input costs $0.30 on Grok 4.5 and $0.20 on Grok 4.3. If your prompts share a stable prefix, caching on the more expensive model can beat switching to the cheaper one outright — worth checking before you migrate anything.
Sources
xAI rates verified 2026-08-05 (source). xAI rates verified 2026-08-05 (source).