Short answer
I could not verify an official free trial specifically for Grok 4 Heavy. The xAI referral documentation describes a two-week Premium trial that requires a payment card, but it does not establish that the trial includes Heavy. The public subscription pricing page does not list a SuperGrok Heavy price, and the public API model catalog does not list Grok 4 Heavy. (techjacksolutions.com)
Do not assume that a Premium trial, a Grok Bot offer, or API access lets you try Heavy unless the offer or documentation names Grok 4 Heavy or SuperGrok Heavy.
What free trial is documented?
The xAI referral documentation describes a two-week trial of Premium and says a payment card is required. It does not establish Heavy access or provide enough information here to confirm the trial’s eligibility conditions, renewal charge, or cancellation deadline. Before entering a card, check the offer’s checkout terms for the plan that starts after the trial, the first-charge date, and how and when to cancel. (xAI referral documentation)
The pricing documentation lists Premium at $30 per month or $300 per year. Those are Premium prices—not Heavy prices—and the available information does not establish which billing option or renewal amount would apply to a particular referral offer. (xAI subscription pricing)
Older third-party reports describe a three-day trial for regular SuperGrok and a seven-day trial for Grok Bot. Neither report establishes current availability or says the offer includes Grok 4 Heavy. (TechJack’s pricing guide; TestingCatalog’s report)
What does SuperGrok Heavy cost?
The public subscription pricing page lists Free, Plus, Premium, Super, Ultra, Teams, and Enterprise; it does not show a SuperGrok Heavy price. Separate xAI documentation refers to some customers getting Grok Bot usage through an existing SuperGrok Heavy subscription connected to Cursor, but that does not establish a current price or a new-customer offer. (xAI pricing; Grok Bot documentation)
Third-party estimates conflict: TechJack reports $300 per month, while Zignuts claims $100 per month. TechJack says its figure was not re-confirmed; neither estimate is a current official quote. Don’t use either as a reliable budget number. Confirm the plan and billing period at checkout before subscribing. (TechJack; Zignuts)
Does the production API offer Grok 4 Heavy?
The public API model catalog recommends Grok 4.7 for general work but does not list Grok 4 Heavy. The public documentation therefore does not establish a production API route, API trial, or API price for Heavy. This does not prove that no private or limited-access route exists; it means the public catalog does not confirm one. (xAI API model catalog)
For comparison, the listed model Grok 4.7 costs $2 per million input tokens and $6 per million output tokens at short context, in USD. A workload using one million input tokens and one million output tokens would cost $8 before tool-call charges. The US regional endpoint has a 10% token-rate premium, making that example $8.80. These are Grok 4.7 rates, not Heavy pricing; tool calls may add charges. (xAI API pricing)
xAI also advertises a free API Playground. The public model information does not establish that it provides Grok 4 Heavy. (xAI API)
Budget takeaway
- Want to try Heavy for free? No current official Heavy-specific trial was verified. Don’t assume the Premium referral trial includes it.
- Considering a subscription? The public pricing page does not show a Heavy price. Check the provider’s checkout for the current price and billing period; treat third-party estimates as unconfirmed.
- Building with an API? The public catalog lists Grok 4.7 at $2/M input and $6/M output tokens, but does not list Heavy. Those rates apply to Grok 4.7 only.
Keep subscription access, API usage, and third-party chatbot offers separate when comparing costs. A free offer is useful for evaluating Heavy only if its terms explicitly name Grok 4 Heavy or SuperGrok Heavy.
Sources
Refer friends to Grok Bot — xAI documentation
Pricing — xAI subscription documentation
Grok Pricing: Definitive Free & Paid Guide 2026
TestingCatalog report on a Grok Bot trial
Grok Bot — xAI subscription documentation
Grok 4 Heavy: Massive Parameter Model for Deep AI Computation
Grok Models & Pricing — xAI developer documentation