rumoredxAIExpected: Q3 2026

Grok 4 Heavy API

Heavy-reasoning variant of Grok 4, similar to the Grok Heavy tier pattern.

What we know

Heavy-reasoning variant of Grok 4, similar to the Grok Heavy tier pattern.

Why it matters: Benchmark-focused developers want access to the highest-intelligence Grok variant as soon as it exists.

Expected pricing: ~$15 / $60 per 1M tokens

Current best equivalent

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GPT-5.4

Closest frontier reasoning model on SkillBoss today.

Use GPT-5.4 Now →Get API Key

We'll auto-switch your API calls to Grok 4 Heavy the moment it launches — no code changes required.

Call it with curl

curl -X POST https://api.skillboss.co/v1/run \
  -H "Authorization: Bearer $SKILLBOSS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "skill_id": "openai/gpt-5.4",
    "input": {
      "prompt": "Say hello from Grok 4 Heavy — routed via SkillBoss"
    }
  }'

Alternate options

ModelSkill IDTradeoff
Claude 4.5 Opusanthropic/claude-4-5-opusBest alternative for long-horizon reasoning

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Disclaimer: SkillBoss is an independent multi-provider gateway and is not affiliated with, endorsed by, or sponsored by xAI. “Grok 4 Heavy”, “xAI”, and all related product names, logos, and trademarks are the property of their respective owners and are referenced here solely for factual comparison purposes. Information on this page is based on public roadmaps, leaks, and industry signals — not an official commitment from xAI. Actual release dates, names, features, and pricing may differ. See our full IP / trademark policy.