Grok 4 Models by xAI
xAIProprietary
14 models2025–2026Up to 2m ctxFrom $0.2/1M input
Details
ResearcherxAI
LicenseProprietary
Commercial useCommercial use: conditional
Models14
Released2025–2026
Max context2m
Capabilities
Vision13 of 14 models
Multimodal13 of 14 models
Reasoning11 of 14 models
Function Calling11 of 14 models
Tool Use11 of 14 models
Structured Outputs9 of 14 models
Code Execution2 of 14 models
About
xAI's Grok 4 model family spans the original Grok 4 API lineup, Grok 4.3, Grok 4.20 variants, and Grok 4.5 — the July 2026 flagship for coding, agentic tasks, and knowledge work.
Current Variants
Use-when guidance is based on each model's tracked capabilities, context window, release date, and replacement status.
9 in view5 retired
Grok 4.5Current
Use when the workload needs code, 500k context, and reasoning.
2026-07code500k contextreasoning
Grok Build 0.1Current
Use when the workload needs code, 256k context, and reasoning.
2026-05code256k contextreasoning
Grok 4.3Current
Use when the workload needs 1m context, reasoning, and tool use.
2026-051m contextreasoningtool use
Grok 4.20 Multi-AgentCurrent
Use when the workload needs agentic, 1m context, and reasoning.
2026-03agentic1m contextreasoning
Grok 4.20 ReasoningCurrent
Use when the workload needs reasoning, 1m context, and tool use.
2026-03reasoning1m contexttool use
Grok 4.20 Non-ReasoningCurrent
Use when the workload needs 1m context, tool use, and function calling.
2026-031m contexttool usefunction calling
Grok 4.20Current
Use when the workload needs 1m context, reasoning, and tool use.
2026-021m contextreasoningtool use
Grok 4.1Current
Use when the workload needs 131k context, reasoning, and tool use.
2025-11131k contextreasoningtool use
Grok 4 HeavyCurrent
Use when the workload needs 256k context and multimodal inputs.
2025-07256k contextmultimodal inputs
| Model | Use when | Released | Signals | Status |
|---|---|---|---|---|
| Grok 4.5 | Use when the workload needs code, 500k context, and reasoning. | 2026-07 | code500k contextreasoning | Current |
| Grok Build 0.1 | Use when the workload needs code, 256k context, and reasoning. | 2026-05 | code256k contextreasoning | Current |
| Grok 4.3 | Use when the workload needs 1m context, reasoning, and tool use. | 2026-05 | 1m contextreasoningtool use | Current |
| Grok 4.20 Multi-Agent | Use when the workload needs agentic, 1m context, and reasoning. | 2026-03 | agentic1m contextreasoning | Current |
| Grok 4.20 Reasoning | Use when the workload needs reasoning, 1m context, and tool use. | 2026-03 | reasoning1m contexttool use | Current |
| Grok 4.20 Non-Reasoning | Use when the workload needs 1m context, tool use, and function calling. | 2026-03 | 1m contexttool usefunction calling | Current |
| Grok 4.20 | Use when the workload needs 1m context, reasoning, and tool use. | 2026-02 | 1m contextreasoningtool use | Current |
| Grok 4.1 | Use when the workload needs 131k context, reasoning, and tool use. | 2025-11 | 131k contextreasoningtool use | Current |
| Grok 4 Heavy | Use when the workload needs 256k context and multimodal inputs. | 2025-07 | 256k contextmultimodal inputs | Current |
Release Timeline
8 release groups2026-07
1 current
Grok 4.5
Currentcode500k contextreasoning
2026-05
2 current
Grok 4.3
Current1m contextreasoningtool use
Grok Build 0.1
Currentcode256k contextreasoning
2026-03
3 current
Grok 4.20 Multi-Agent
Currentagentic1m contextreasoning
Grok 4.20 Non-Reasoning
Current1m contexttool usefunction calling
Grok 4.20 Reasoning
Currentreasoning1m contexttool use
2026-02
1 current
Grok 4.20
Current1m contextreasoningtool use
2025-11
1 current · 1 retired
Grok 4.1
Current131k contextreasoningtool use
Grok 4.1 Fast
Replaced2m contextreasoningtool use
2025-09
2 retired
Grok 4 Fast Non-Reasoning
Replaced2m contextreasoningmultimodal inputs
Grok 4 Fast Reasoning
Replaced2m contextreasoningmultimodal inputs
2025-08
1 retired
Grok Code Fast 1
Replacedcode262k context314B parameters
2025-07
1 current · 1 retired
Grok 4
Replaced256k contextreasoningtool use
Grok 4 Heavy
Current256k contextmultimodal inputs
Replaced By
Replaced
Keep for legacy integrations; evaluate Grok 4.3 before new work.
Replaced
Keep for legacy integrations; evaluate Grok 4.3 before new work.
Keep for legacy integrations; evaluate Grok 4.3 before new work.
Replaced
Keep for legacy integrations; evaluate Grok Build 0.1 before new work.
Specifications(14 models)
| Model | Released | Context | Parameters | Vision | Multimodal | Reasoning | Fn Calling | Tool Use | Structured Outputs | Code Exec |
|---|---|---|---|---|---|---|---|---|---|---|
| Grok 4.5 | 2026-07 | 500k | — | Yes | Yes | Yes | Yes | Yes | No | Yes |
| Grok Build 0.1 | 2026-05 | 256k | — | Yes | Yes | Yes | Yes | Yes | Yes | No |
| Grok 4.3 | 2026-05 | 1m | ~0.5T | Yes | Yes | Yes | Yes | Yes | Yes | No |
| Grok 4.20 Multi-Agent | 2026-03 | 1m | — | Yes | Yes | Yes | Yes | Yes | Yes | No |
| Grok 4.20 Reasoning | 2026-03 | 1m | — | Yes | Yes | Yes | Yes | Yes | Yes | No |
| Grok 4.20 Non-Reasoning | 2026-03 | 1m | — | Yes | Yes | No | Yes | Yes | Yes | No |
| Grok 4.20 | 2026-02 | 1m | — | Yes | Yes | Yes | Yes | Yes | Yes | No |
| Grok 4.1 | 2025-11 | 131k | — | Yes | Yes | Yes | Yes | Yes | No | No |
| Grok 4 Heavy | 2025-07 | 256k | — | Yes | Yes | No | No | No | No | No |
Available From(7 providers)
Pricing
| Model | Provider | Input / 1M | Output / 1M | Type |
|---|---|---|---|---|
| Grok Build 0.1 | xAI Console | $1 | $2 | Serverless |
| Grok Build 0.1 | Vercel AI Gateway | $1 | $2 | Serverless |
| Grok Build 0.1 | OpenRouter | $1 | $2 | Serverless |
| Grok 4.20 | xAI Console | $1.25 | $2.5 | Serverless |
| Grok 4.3 | xAI Console | $1.25 | $2.5 | Serverless |
| Grok 4.20 Multi-Agent | xAI Console | $1.25 | $2.5 | Serverless |
| Grok 4.3 | OpenRouter | $1.25 | $2.5 | Serverless |
| Grok 4.20 | OpenRouter | $1.25 | $2.5 | Serverless |
| Grok 4.20 Reasoning | xAI Console | $1.25 | $2.5 | Serverless |
| Grok 4.20 Non-Reasoning | xAI Console | $1.25 | $2.5 | Serverless |
| Grok 4.20 Multi-Agent | Vercel AI Gateway | $1.25 | $2.5 | Serverless |
| Grok 4.20 Non-Reasoning | Vercel AI Gateway | $1.25 | $2.5 | Serverless |
| Grok 4.20 Reasoning | Vercel AI Gateway | $1.25 | $2.5 | Serverless |
| Grok 4.3 | Vercel AI Gateway | $1.25 | $2.5 | Serverless |
| Grok 4.3 | AWS Bedrock | $1.25 | $2.5 | Serverless |
| Grok 4.20 Multi-Agent | OpenRouter | $2 | $6 | Serverless |
| Grok 4.5 | xAI Console | $2 | $6 | Serverless |
| Grok 4.5 | OpenRouter | $2 | $6 | Serverless |
| Grok 4.5 | Vercel AI Gateway | $2 | $6 | Serverless |
Popular comparisons in this family
Comparisons
- GPT-4o (08-06) vs Grok 4
- o3 vs Grok 4
- Grok 4 Fast Reasoning vs o3
- Grok 4.3 vs GPT-5.5
- Claude Sonnet 4.6 vs Grok 4
- Claude Opus 4.6 vs Grok 4
- Grok 4 Fast Reasoning vs Claude Opus 4.6
- Claude Fable 5 vs Grok 4
Frequently Asked Questions
- What is Grok 4 used for?
- Grok 4 is used for code, agentic, and reasoning. The family description and listed model capabilities point to those workloads as the best fit.
- How does Grok 4 compare to Grok 1?
- Grok 4 by xAI is strongest where you need code, while Grok 1 by xAI is the closest related family to check for reasoning. Grok 4 has 14 listed variants and reaches up to 2m context, so compare the specs and pricing tables before choosing a production model.
- Which Grok 4 model should I use?
- For the lowest listed input price, start with Grok 4.1 Fast through OpenRouter at $0.2/1M input tokens. For the most capable/latest local choice, evaluate Grok 4.3 with 1m context and reasoning, tool use, function calling, structured outputs, and multimodal inputs.
Related Model Families
Models(14)
Grok 4.5
2026-07500k3 providers
MultimodalReasoning
Grok Build 0.1
2026-05256k3 providers
MultimodalReasoning
Grok 4.3
2026-051m~0.5T5 providers
MultimodalReasoning
Grok 4.20 Multi-Agent
2026-031m3 providers
MultimodalReasoning
Grok 4.20 Reasoning
2026-031m2 providers
MultimodalReasoning
Grok 4.20 Non-Reasoning
2026-031m2 providers
Multimodal
Grok 4.20
2026-021m2 providers
MultimodalReasoning
Grok 4.1
2025-11131k
MultimodalReasoning
Grok 4 Heavy
2025-07256k
Multimodal