Grok 4.20
3258°
Run this model
Offers / Ads
SpaceXAI | 2,000,000 token context | $1.25/M input, $2.50/M output. 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 consistently precise and truthful responses. Reasoning can be enabled/disabled using the reasoning enabled parameter in the API. Learn more in our docsOpens in new tab
Guides for this model
Open weights vs open source vs API-only: what you are actually allowed to do
How to choose an AI model in October 2026: the closed source news, then the open weights worth downloading
The 10 cheapest ChatGPT alternatives in 2026: free local models, free tiers and flat-rate plans
Captain's notes
Notes from 2026-10-13
Grok 4.20 is a closed-weights reasoning model from SpaceXAI with a two-million-token context window and toggleable chain-of-thought via the API. SpaceXAI positions it on low hallucination rates and tight prompt adherence, with agentic tool-calling built in. At $1.25 per million input tokens it sits at the cheaper end of frontier reasoning models, making it worth a look if you need long-context reasoning without a punishing bill.
Known for
- Two-million-token context window — one of the largest available
- Reasoning can be switched on or off per request through the API
- Built-in agentic tool calling for multi-step workflows
- SpaceXAI claims low hallucination rate and strict prompt adherence
- Vision support alongside text
Watch out for
- Closed weights only — no local deployment, no offline use, no fine-tuning
- SpaceXAI has not published independent benchmark results to verify hallucination claims
- Output tokens cost twice the input rate; long reasoning traces can add up quickly
Prompts to try
Multi-step research plan
I need to understand the competitive dynamics of the solid-state battery market by 2030. Identify the three most important technical bottlenecks, name the companies closest to solving each one, and produce a one-page briefing with a recommended monitoring strategy for a non-specialist executive.
Agentic data pipeline design
Design an agentic workflow that monitors a public RSS feed for mentions of a specific company, extracts the headline, publication date and sentiment, deduplicates entries, and writes clean rows to a SQLite database. List each tool call the agent needs to make and describe the failure-handling logic.
Vision document audit
I'm attaching a dense technical specification document as an image. Extract every numbered requirement, flag any that are ambiguous or internally contradictory, and return the results as a structured table with columns: requirement ID, text, issue type, suggested clarification.
Compare with
- Grok 4.7API-only model500,000 token context · $2.00/M input, $6.00/M output
- Grok 4.6API-only model500,000 token context · $2.00/M input, $6.00/M output
- Grok 4.5API-only model500,000 token context · $2.00/M input, $6.00/M output
- Grok Build 0.1API-only model256,000 token context · $1.00/M input, $2.00/M output
More text models from x-ai
Questions people ask
- Can I run Grok 4.20 locally?
- No. Grok 4.20 is API-only with no open weights released, so local deployment is not possible.
- What does Grok 4.20 cost and how large is the context?
- Pricing is $1.25 per million input tokens and $2.50 per million output tokens, with a two-million-token context window.
- How does Grok 4.20 differ from other Grok models?
- Grok 4.20 adds a two-million-token context window and a toggleable reasoning mode via an API parameter; SpaceXAI has not published a direct comparison to sibling models such as Grok 4.7.
Captain's verdictA genuinely long-context reasoning model at a reasonable input price — worth testing if your work involves large documents or multi-step agents, once you accept the closed-weights lock-in.
Captain writes these notes from the model's own description and model card. Prices and context sizes are the provider's at the time of writing and can change.
Ranking badge
Updated Oct 22, 2026
Made this model? Show this badge on your page.
Paste it into your Hugging Face card or Civitai description.
How this score adds up
This model has no popularity data from any source yet, so it carries a stand-in number below 7,000° that keeps the lists complete. It never ranks above a model with data. The breakdown appears here as soon as a source reports it.
Glossary: the terms used here
- Heat score
- One number for how much a model is used and wanted right now, from 0° to 9,999°. Every list on this site that says hottest is sorted by it and nothing else.
- Floor
- The 7,000° every model with real data starts from. The scale runs from 0° to 9,999°; the part below the floor is reserved for stand-ins (models without data), so that a model with data always ranks above one without. The floor is the same for everyone and decides nothing; the degrees above it are the measurement.
- Download-equivalents
- Everything the score treats as a download, added up: downloads themselves, each torrent seeder as 1,000, each AI Horde image and each run on a generation site as one.
- Log scale
- Counting by tens, not by ones: going from 1,000 to 10,000 downloads adds the same degrees as going from 10,000 to 100,000. It keeps giants from crowding out everything else.
- Likes
- Thumbs up and likes from every source, worth half a download each on the log scale.
- Adoption rate
- How many downloads a day a model gets right now, from the difference between two readings of a source. A quarter of the weight of the download term.
- Measured and estimated
- Measured means two readings of a source exist and the difference is real. Estimated means only today's total is known and the past is spread over the model's life; the site says which one it is showing.
- Seeder
- Someone who keeps a copy of the weights online for others to download over a torrent, or a hosted mirror doing the same. Each one counts as 1,000 downloads.
- AI Horde
- A volunteer network that generates images for free on donated computers. The number of images it has made with a model is public, and each counts as one download.
- Generation sites
- Sites that host their own copies of a model and let people generate with it, such as PixAI, SeaArt and Yodayo. Their downloads count like Civitai's and each generation run as one download.
- OpenRouter tokens
- A text model served through an API, such as Claude or GPT, has no weights to download, so its usage is measured in tokens: the pieces of text it read and wrote through OpenRouter, a gateway many apps use, over the last 30 days. Every 10,000,000 tokens count as one download. Source: OpenRouter (openrouter.ai/rankings), CC BY 4.0.
- Full model (checkpoint)
- The weights themselves, the file that generates on its own. It gets a bonus because add-ons depend on it.
- LoRA and embedding
- Small add-on files that steer someone else's weights toward a style, a character or a concept. They cannot run alone.
- Family and weights
- The base a model is built on, such as SD 1.5, SDXL, Flux or Wan. Every model inherits the release date of its family's weights.
- Age
- Degrees taken off for how long ago the family's weights came out: 150° a year, up to 750°. It keeps old downloads that had years to pile up from freezing the top of the list.
- Family boost
- A small, bounded nudge for LoRAs of a family this site is pushing forward right now, always listed in the breakdown.
- Stand-in score
- A stable number below the floor given to a model no source reports on yet, so lists stay complete. It never ranks above a model with data.
- New! (grace period)
- A model less than 7 days old shows New! instead of a score and holds no place in the rankings. Its score is computed from day one, but a model one day old grows faster than anything, so without the wait the week's #1 would always be whatever came out yesterday rather than what held up for a week.
- Trend
- How a model's growth over a period compares with the typical model's growth over the same period. Faster than typical reads as a rise, slower as a fall.
- Typical model
- The middle of the catalog: half the models with a figure grew faster over the period, half slower.
Grok 4.20 is a text model for the Text / LLM family listed on ModelTrends.ai, a read-only catalog of open source AI image, video and text models. Compare it with other Text / LLM models and check its heat score to see how it is trending.
Browse by Model Family
Text / LLM Models
434
Anima Models
528
Chroma Models
19
Fibo Models
2
Flux Models
1,496
Flux 2 / Klein Models
1,239
Flux 3 Models
3
Moss Models
3
Iris Models
1
MiniMax H3 Models
364
Hunyuan Models
204
Ideogram Models
20
Krea2 Models
717
Qwen Models
20
Qwen2 Models
47
Ltx2 Models
153