Grok 4.1 Fast vs Grok 4.3
Benchmarks, API pricing and specs, head to head. Data updated 2026-06-10.
Grok 4.1 Fast
xAI · Nov 2025
A 2M-token context window for $0.20 per million input tokens — the cheapest long-context frontier offering anywhere.
Grok 4.3
xAI · Apr 2026
xAI's frontier model: 1M context at $1.25/$2.50, ~168 tokens/sec, and a record low hallucination rate on independent testing.
The verdict
These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: Grok 4.1 Fast works out roughly 5.7x cheaper per blended million tokens. Grok 4.1 Fast also takes 2M of context versus 1M for Grok 4.3.
Specs & pricing
| Grok 4.1 Fast | Grok 4.3 | |
|---|---|---|
| modhub Index | — | — |
| Input price / 1M | $0.2 | $1.25 |
| Output price / 1M | $0.5 | $2.5 |
| Context window | 2M | 1M |
| Max output | — | — |
| Open weights | no | no |
| Reasoning model | yes | yes |
| Multimodal input | text, image | text, image |
| Knowledge cutoff | Nov 2025 | Mar 2026 |
| Released | Nov 2025 | Apr 2026 |
| Example monthly cost* | $2.75 | $16.25 |
* 10M input + 1.5M output tokens per month at list prices, no caching. Green = better value on that row.
Frequently asked questions
- Which is better, Grok 4.1 Fast or Grok 4.3?
- These two models don't yet share verified results on the benchmarks we track, so judge them on specs, pricing and intended use. On price the gap is dramatic: Grok 4.1 Fast works out roughly 5.7x cheaper per blended million tokens. Grok 4.1 Fast also takes 2M of context versus 1M for Grok 4.3.
- Which is cheaper, Grok 4.1 Fast or Grok 4.3?
- Grok 4.1 Fast costs $0.2/$0.5 per million input/output tokens, while Grok 4.3 costs $1.25/$2.5. For a typical workload of 10M input and 1.5M output tokens per month, that's $2.75 versus $16.25.
- Which model is better for coding, Grok 4.1 Fast or Grok 4.3?
- We don't yet track SWE-bench Verified results for both models; check their individual pages for coding-related scores.