xAI · Grok 4 Fast (reasoning)
grok-4-fast-reasoning- Releasedunknown
- Deprecated
- Retired
Tags
Editorial tags reflect our assessment; documented tags are backed by the sources below.
Specifications
- Input price
- unknown
- Output price
- unknown
- Price class
- unknown
- Context window
- unknown
- Max output
- unknown
- Released
- unknown
- Input modalities
- text
- Output modalities
- text
- Knowledge cutoff
- unknown
- Tool use
- unknown
- Structured output
- unknown
- License
- unknown
- Maker
- xAI
Use it for
No editorial profile yet — the specifications and derived alternatives below are generated from the data.
Alternatives
What to use instead. Curated suggestions are written by our editors for this model; derived ones are ranked automatically from tags, tier and price class.
- Grok 4.20 (reasoning)derived
xAI
grok-4.20-0309-reasoningSame provider, same tier (mid-tier); shares chat, coding, reasoning and agents.
In $1.25 / M tokOut $2.50 / M tok
ActiveTextChatCoding+5 - Claude Sonnet 4.5derived
Amazon Bedrock
anthropic.claude-sonnet-4-5-20250929-v1:0Alternative from Amazon Bedrock, same tier (mid-tier); shares chat, coding, reasoning and agents.
In $3.00 / M tokOut $15.00 / M tok
ActiveTextVision
Change history
Nothing has changed since this model was first recorded — no status change and no price change.
Price history
No price changes recorded yet.
Sources & verification
Facts
Status, dates, pricing and specifications were verified against these pages.
Last verified: (2026-09-10 12:00) · ✓ verified