Grok 4.20
xAIdocs.x.ai/developers/models/grok-4.20-0309-reaso
Grok 4.20 is a reasoning model from SpaceXAI with industry-leading speed and agentic tool calling capabilities. It combines the lowest hallucination rate on the market with strict prompt adherance, delivering...
Updated 26 min ago · first seen 11 Sept 2026
model_01M294WW257REBD60NE44YGEZQ
- Context
- 1M tokens
- T1 · 31 min ago
- Released
- 31 Mar 2026
- T2 · 2 h ago
- Knowledge cutoff
- Sept 2025
- T2 · 2 h ago
Specification
- Family
- Grok
Source:xAI — docsT1observed 31 min agohigh
- Release date
- 31 Mar 2026
Source:OpenRouter public model & pricing listingT2observed 2 h agomedium
- Status
- deprecated
Source:Artificial AnalysisT2observed 26 min agomedium
- Openness
- proprietary
Source:Artificial AnalysisT2observed 26 min agomedium
- Context window
- 1M tokens
Source:xAI — docsT1observed 31 min agohigh
- Max output
- 1.8M tokens
Source:OpenRouter public model & pricing listingT2observed 2 h agomedium
- Knowledge cutoff
- Sept 2025
Source:OpenRouter public model & pricing listingT2observed 2 h agomedium
- Modalities
- image, text
Source:OpenRouter public model & pricing listingT2observed 2 h agomedium
- Input modalities
- text, image
Source:xAI — docsT1observed 31 min agohigh
- Output modalities
- text
Source:OpenRouter public model & pricing listingT2observed 2 h agomedium
- Tokenizer
- Grok
Source:OpenRouter public model & pricing listingT2observed 2 h agomedium
- API model id
- grok-4.20-0309-reasoning
Source:xAI — docsT1observed 31 min agohigh
- Official page
Source:xAI — docsT1observed 31 min agohigh
- Batch api
- Yes
Source:xAI — docsT1observed 30 min agohigh
- File input
- Yes
Source:OpenRouter public model & pricing listingT2observed 2 h agomedium
- Aa median output tokens per second
- 101.1
Source:Artificial AnalysisT2observed 26 min agomedium
- Openrouter id
- x-ai/grok-4.20
Source:OpenRouter public model & pricing listingT2observed 2 h agomedium
- Regions
- us-east-1, us-west-2
Source:xAI — docsT1observed 31 min agohigh
- Supported parameters
- include_reasoning, logprobs, max_tokens, reasoning, response_format, seed, structured_outputs, temperature, tool_choice, tools, top_logprobs, top_p
Source:OpenRouter public model & pricing listingT2observed 2 h agomedium
Each value shows its source, tier and observation time. Conflicting claims are kept side by side and flagged — never averaged. How AI Atlas records facts →
Provenance
Attributed facts
24
Source tiers
T1T27 / 17
Freshest observation
26 min ago
Conflicts
1 flagged
Modalities
- Modalities
- imagetext
- Input
- textimage
- Output
- text
Capabilities
Tool calling
Yes
OpenRouter public model & pricing listing · T2
Structured output
Yes
OpenRouter public model & pricing listing · T2
Reasoning
Yes
OpenRouter public model & pricing listing · T2
Vision
Yes
OpenRouter public model & pricing listing · T2
Audio
Unavailable
Fine-tuning available
Unavailable
- Context window
- 1M tokens
Source:xAI — docsT1observed 31 min agohigh
- Max output
- 1.8M tokens
Source:OpenRouter public model & pricing listingT2observed 2 h agomedium
- Knowledge cutoff
- Sept 2025
Source:OpenRouter public model & pricing listingT2observed 2 h agomedium
- Tokenizer
- Grok
Source:OpenRouter public model & pricing listingT2observed 2 h agomedium
| Benchmark | Score | Metric | Config | Evaluated | Source |
|---|---|---|---|---|---|
| τ²-bench | 92.98% | pass^1 | aa_slug=grok-4-20 · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| Artificial Analysis Intelligence Index | 25.66 | index | aa_slug=grok-4-20 · version=4.3 · estimated=true | — | artificialanalysis.aiT2 |
| GPQA | 91.11% | accuracy | aa_slug=grok-4-20 · variant=GPQA Diamond · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| Humanity's Last Exam | 34.52% | accuracy | aa_slug=grok-4-20 · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| IFBench | 81.22% | accuracy | aa_slug=grok-4-20 · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| MMMU-Pro | 74.57% | accuracy | aa_slug=grok-4-20 · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
| Terminal-Bench | 37.88% | accuracy | aa_slug=grok-4-20 · variant=hard · evaluator=Artificial Analysis · index_version=4.3 | — | artificialanalysis.aiT2 |
Scores are reported as published, with their evaluation configuration (harness, prompting, judge). Results with different configs are not directly comparable — see methodology.
Current prices
| Provider | Input / 1M | Output / 1M | Cached in | Batch in / out | Context | Observed | Source |
|---|---|---|---|---|---|---|---|
| xAI APIx-ai/grok-4.20 | $1.25 | $2.5 | $0.20 | — | 2M | 31 min ago | openrouter.aiT2 |
| xAI APIgrok-4.20-0309-reasoning | $1.25 | $2.5 | $0.20 | $1 / $2 | 1M | 31 min ago | docs.x.aiT1 |
USD per 1M tokens as published by each provider (USD). Rows are append-only: every change is kept in the history below.
Available through 1
Price history
Input price · USD / 1M tokens
Output price · USD / 1M tokens
- xAI API
No hardware estimate available
No lineage recorded
Papers 0
No papers linked yet.
Repositories 0
No repositories linked yet.
As of
Rewind the record: see this entity's attributes exactly as AI Atlas knew them on a given day.
Claim history · Max output
Max outputmax_output_tokens1
| Value | Valid from → to | Status | Source | Confidence | Extractor |
|---|---|---|---|---|---|
| 1.8M tokens | → current | current | OpenRouter public model & pricing listingT2 | medium | deterministic |
Claims are temporal and append-only: a new observation closes the previous claim (valid_to) instead of overwriting it. Conflicting claims from different sources are kept side by side and flagged — never averaged. Methodology →
Grok 4.20 scores 25.66 on Artificial Analysis Intelligence Index
artificial_analysisGrok 4.20: context length changed from 2000000 to 1000000
Context window2M tokens→1M tokensxaiGrok 4.20: modalities input changed from ["image", "text"] to ["text", "image"]
Input modalitiesimage, text→text, imagexaixAI API lists Grok 4.20 at $1.25 in / $2.5 out per 1M tokens
openrouter
| Source | Document | Type | Tier | Last observed | Snapshots |
|---|---|---|---|---|---|
| xAI — docs | docs.x.ai/developers/models/grok-4.20-0309-reasoning.md | model_page | T1· Official | 30 min ago | 1 |
| xAI — docs | docs.x.ai/developers/models | model_docs | T1· Official | 31 min ago | 1 |
| Artificial Analysis | artificialanalysis.ai/leaderboards/models | leaderboard | T2· Quality secondary | 26 min ago | 1 |
| OpenRouter public model & pricing listing | openrouter.ai/api/v1/models | catalogue | T2· Quality secondary | 31 min ago | 2 |
Tier 1 = official/primary, 2 = quality secondary, 3 = community, 4 = unverified. Every snapshot is archived; see all sources and the methodology.