Grok 4.6 vs Grok Code Fast 1

xAI · US  |  xAI · US · Updated June 2026

Quick verdict

Both are xAI models. Grok 4.6 is the newer, generally stronger default; reach for Grok Code Fast 1 when its lower price or a specific cost or latency profile matters more than the latest capabilities.

Grok 4.6 and Grok Code Fast 1 are both xAI models, so the real question is not which lab to trust but which tier fits your workload and budget. Grok 4.6 is xAI's Grok 4.6 - frontier-level intelligence (AA Index 61, tying GPT-5.6 Sol) at a fraction of flagship pricing, and already in Cursor and Copilot. Grok Code Fast 1 is xAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality. Since both come from the same lab, the comparison below focuses on the tier-and-cost trade-offs that actually separate them.

Key differences at a glance

Side-by-side specs

SpecGrok 4.6Grok Code Fast 1
ProviderxAI (US) xAI (US)
ReleasedAugust 12, 2026 August 28, 2025
Context window500K (~750 pages) 256K (~384 pages)
Price (in/out)$2/$6 per 1M tokens $0.2/$1.5 per 1M tokens
Open weight?No — API only No — API only
Modalitiestext, image, code text, code
SWE-Bench VerifiedNot published Not published
MRCR v2 @ 1MNot published Not published

Who wins what

Frontier-tier intelligence at a value price - Artificial Analysis Intelligence Index 61, tying GPT-5.6 Sol

Grok 4.6

Grok Code Fast 1 is comparatively weak here — a speed-tier coding model, not a frontier reasoner

Ranked #2 on Artificial Analysis's independent GDPval agentic test, behind only Claude Opus 5

Grok 4.6

XAI's Grok 4.6 - frontier-level intelligence (AA Index 61, tying GPT-5.6 Sol) at a fraction of flagship pricing, and already in Cursor and Copilot — and it carries the larger 500K context.

$2/$6 per million tokens - a fraction of Claude Opus 5 or GPT-5.6 Sol

Grok 4.6

Its 500K window holds about 2× more than Grok Code Fast 1's 256K in a single prompt.

Fast, cheap agentic coding at $0.20/$1.50

Grok Code Fast 1

At $0.2/$1.5 per 1M tokens it undercuts Grok 4.6 ($2/$6 per 1M tokens), and that gap compounds at volume.

Low-latency code generation and terminal tasks

Grok Code Fast 1

XAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality — and it runs cheaper at $0.2/$1.5 per 1M tokens.

High-volume coding pipelines where speed beats peak quality

Grok Code Fast 1

Grok 4.6 is comparatively weak here — coding gains (DeepSWE 65.9, APEX-Agents 57.5) are xAI's own numbers, not independently reproduced

Lowest cost at scale

Grok Code Fast 1

At $0.2/$1.5 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.

Largest single-prompt input

Grok 4.6

Its 500K window is about 2× larger than Grok Code Fast 1's 256K, fitting roughly 750 pages in one prompt.

Which should you pick?

A cost-sensitive startup shipping high volume

Grok Code Fast 1

At $0.2/$1.5 per 1M tokens it undercuts Grok 4.6, and on millions of tokens that margin decides the monthly bill.

Someone analysing very long documents or codebases

Grok 4.6

Larger 500K window fits more in one prompt.

Anyone whose priority is frontier-tier intelligence at a value price - artificial analysis intelligence index 61, tying gpt-5.6 sol

Grok 4.6

It is specifically built for that.

Anyone whose priority is fast, cheap agentic coding at $0.20/$1.50

Grok Code Fast 1

That is its strongest area.

Grok 4.6: where it fits

XAI's Grok 4.6 - frontier-level intelligence (AA Index 61, tying GPT-5.6 Sol) at a fraction of flagship pricing, and already in Cursor and Copilot. Released August 12, 2026 by xAI, it is built for frontier-tier intelligence at a value price - Artificial Analysis Intelligence Index 61, tying GPT-5.6 Sol, ranked #2 on Artificial Analysis's independent GDPval agentic test, behind only Claude Opus 5, $2/$6 per million tokens - a fraction of Claude Opus 5 or GPT-5.6 Sol, and 500K-token context; available same-day in Cursor and (two days later) GitHub Copilot.

Its trade-offs are real: coding gains (DeepSWE 65.9, APEX-Agents 57.5) are xAI's own numbers, not independently reproduced, parameter count is undisclosed, text and image input only - not a full multimodal model, and fast-moving target: xAI says Grok 4.7 is only weeks away. At $2 in / $6 out per million tokens, it sits in the mid price band.

Grok Code Fast 1: where it fits

XAI's speed-tier coding model at $0.20/$1.50 with a 256K window — cheap, fast agentic code over frontier quality. Released August 28, 2025 by xAI, it is built for fast, cheap agentic coding at $0.20/$1.50, low-latency code generation and terminal tasks, high-volume coding pipelines where speed beats peak quality, and a 256K window sized for real codebases.

Its trade-offs: text and code only — no image, audio or video input, xAI did not publish a SWE-Bench Verified score, a speed-tier coding model, not a frontier reasoner, and narrow focus — built for code, not general knowledge work. At $0.2 in / $1.5 out per million tokens, it sits in the budget price band.

The bottom line for this matchup

Because Grok 4.6 and Grok Code Fast 1 come from the same lab (xAI), they share the same training philosophy and ecosystem — the decision is purely tier vs. cost. Grok 4.6 is the more capable, more recent option; the other earns its place only when its price or latency profile fits a specific job better. Most teams should default to Grok 4.6 and drop down only with a concrete reason.

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See pricing

Frequently asked questions

Is Grok 4.6 or Grok Code Fast 1 better for coding?

Public SWE-Bench figures are not available for either model, so the honest test is your own repository — run an identical real bug through both. By design, Grok 4.6 leans toward frontier-tier intelligence at a value price - artificial analysis intelligence index 61, tying gpt-5.6 sol while Grok Code Fast 1 leans toward fast, cheap agentic coding at $0.20/$1.50, and that positioning usually predicts which feels better on your codebase.

Which is cheaper, Grok 4.6 or Grok Code Fast 1?

Grok Code Fast 1 is cheaper — $2/$6 per 1M tokens vs $0.2/$1.5 per 1M tokens, roughly 10× apart on input.

Which has the bigger context window?

Grok 4.6 — 500K vs 256K, about 2× larger. Useful only if the model actually reasons over the full window, which not all do.

Should I upgrade from Grok Code Fast 1 to Grok 4.6?

Since both are xAI models, the newer one (Grok 4.6) is usually the better default unless you need a specific cost or latency profile from the other.

Which is newer, Grok 4.6 or Grok Code Fast 1?

Grok 4.6 — released August 12, 2026, about 12 months after Grok Code Fast 1.

Related comparisons

Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.