Grok 4.1 Fast Reasoning API pricing
Google Vertex AI · chat model · 128K context · ranked #600 of 1809 by input price
What Grok 4.1 Fast Reasoning costs in practice
Grok 4.1 Fast Reasoning is priced at $0.2 per million input tokens and $0.5 per million output tokens , with cached input billed at $0.05 per million — roughly 75% cheaper than fresh input, which matters if your app resends a large system prompt. Against the median priced chat model ($0.5/1M in), this sits at 2.50× cheaper.
Monthly cost examples
Assuming 1,200 prompt + 400 completion tokens per request unless noted, billed 30 days a month and without cache hits.
| Workload | Cost / month | Cost / day |
|---|---|---|
| 1,000 requests/day | $13.2 | $0.44 |
| 10,000 requests/day | $132 | $4.4 |
| 100,000 requests/day | $1320 | $44 |
| 1M summaries/month | $1749.98 | $58.33 |
Model a different profile in the cost calculator.
Capabilities
Cheaper alternatives
Ranked by blended cost (3× input + 1× output) — cheaper, but check context and capabilities before switching.
| # | Model | Provider | Input $/1M | Output $/1M | Cached $/1M | Context |
|---|---|---|---|---|---|---|
| 1 | Gemini Exp 1114 | Google Gemini | free | free | — | 1.0M |
| 2 | Gemini Exp 1206 | Google Gemini | free | free | — | 2.1M |
| 3 | Gemma 3 27b It | Google Gemini | free | free | — | 131K |
| 4 | Gemma 4 26b A4b It | Google Gemini | free | free | — | 262K |
| 5 | Gemma 4 31b It | Google Gemini | free | free | — | 262K |
| 6 | Learnlm 1.5 Pro Experimental | Google Gemini | free | free | — | 33K |
Data provenance
This page is assembled from the sources below. Where two sources disagree, both are shown.
Only one source publishes this model; no independent cross-check available yet.
More from Google Vertex AI
Frequently asked
› How much does Grok 4.1 Fast Reasoning cost per 1,000 tokens?
About $0.0002 for input and $0.0005 for output tokens, based on the per-million rates on this page.
› Is Grok 4.1 Fast Reasoning cheaper than other models?
By input price it ranks #600 of 1809 priced chat models in this index, putting it in the cheaper half of the market.
› How often is Grok 4.1 Fast Reasoning's price checked?
The dataset was last refreshed 2026-09-13 13:40 UTC. Providers can change pricing at any time — verify with Google Vertex AI before committing to a budget.