Grok 4.1 Fast
Ultra-cheap, large-context (2M) variant; among the lowest-priced frontier-adjacent APIs in 2026.
Grok 4.1 Fast strengths
- Extremely low cost
- 2M token context
- Fast latency
- Aggressive cache discount
Pricing & context
| Context window | 2M tokens |
| Input price /1M | $0.20 ($0.05 cached) |
| Output price /1M | $0.50 |
| Modalities | text, image |
Cost guide: a typical call of ~10K input + 2K output tokens runs roughly $0.20 ($0.05 cached) × 0.01 + $0.50 × 0.002 — worth modelling against cheaper tiers before committing high-volume traffic.
When to choose Grok 4.1 Fast
Grok 4.1 Fast is best for Large-context, high-volume agentic workloads where cost and context size dominate. If your workload is more cost-sensitive, weigh it against Llama 4 Scout (~$0.08 (varies by host) input /1M) first.
Grok 4.1 Fast FAQ
How much does Grok 4.1 Fast cost?
Grok 4.1 Fast is priced at $0.20 ($0.05 cached) per 1M input tokens and $0.50 per 1M output tokens (public API list price), with a 2M tokens context window.
What is Grok 4.1 Fast best for?
Grok 4.1 Fast by xAI is best for Large-context, high-volume agentic workloads where cost and context size dominate.
Is Grok 4.1 Fast multimodal?
Grok 4.1 Fast supports text, image.
Tools that use Grok 4.1 Fast
Other models
All models →| 01 | GPT-5.5 | OpenAI | $5.00 | → |
| 02 | GPT-5.4 | OpenAI | $2.50 | → |
| 03 | GPT-5.4 mini | OpenAI | $0.75 | → |
| 04 | Claude Opus 4.8 | Anthropic | $5.00 | → |