Pick Gemini 3.1 Pro for largest mainstream production context (2m) or long video and document analysis. Pick Grok 4 for 2m production context window or real-time data via x integration. On a tight budget at scale, Grok 4 is the value pick.
Gemini 3.1 Pro (Google) and Grok 4 (xAI) are two of the models people most often weigh against each other in 2026. Gemini 3.1 Pro is a 2M-token multimodal workhorse — huge breadth, but recall fades deep in the window. Grok 4 is xAI's 2M-context model with live data access and strong reasoning chops. Their biggest split is price, and the breakdown below shows exactly how that plays out for your workload.
Key differences
Price: Grok 4 is about 4× cheaper on input ($3/$15 per 1M tokens vs $12/$18 per 1M tokens) — meaningful once you are processing millions of tokens a month.
Context window: both advertise 2M (~3,000 pages). Tie on paper — test on your own long inputs, since usable recall varies by model.
Recency: Gemini 3.1 Pro is the newer model by about 7 months (released February 2026), usually meaning fresher training data and capabilities.
Specifications
Spec
Gemini 3.1 Pro
Grok 4
Provider
Google (US)
xAI (US)
Released
February 2026
2025
Context window
2M (~3,000 pages)
2M (~3,000 pages)
Price (in/out)
$12/$18 per 1M tokens
$3/$15 per 1M tokens
Open weight?
No — API only
No — API only
Modalities
text, image, audio, video, code
text, image, code
SWE-Bench Verified
Not published
Not published
MRCR v2 @ 1M
26.3%
Not published
Who wins what
Largest mainstream production context (2M): Gemini 3.1 Pro — A core design strength of Gemini 3.1 Pro.
Long video and document analysis: Gemini 3.1 Pro — A core design strength of Gemini 3.1 Pro.
Agentic reasoning (high ARC-AGI-2): Gemini 3.1 Pro — A core design strength of Gemini 3.1 Pro.
2M production context window: Grok 4 — A core design strength of Grok 4.
Real-time data via X integration: Grok 4 — A core design strength of Grok 4.
Strong academic reasoning: Grok 4 — A core design strength of Grok 4.
Lowest cost at scale: Grok 4 — At $3/$15 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.
Which should you pick?
A cost-sensitive startup shipping high volume: Grok 4 — At $3/$15 per 1M tokens it undercuts Gemini 3.1 Pro, and on millions of tokens that margin decides the monthly bill.
Anyone whose priority is largest mainstream production context (2m): Gemini 3.1 Pro — It is specifically built for that.
Anyone whose priority is 2m production context window: Grok 4 — That is its strongest area.
Gemini 3.1 Pro: where it fits
A 2M-token multimodal workhorse — huge breadth, but recall fades deep in the window. Released February 2026 by Google, it is built for largest mainstream production context (2M), long video and document analysis, agentic reasoning (high ARC-AGI-2), and multimodal understanding.
Its trade-offs are real: long-context recall drops sharply past 256K, and premium price per token. At $12 in / $18 out per million tokens, it sits in the premium price band.
Grok 4: where it fits
XAI's 2M-context model with live data access and strong reasoning chops. Released 2025 by xAI, it is built for 2M production context window, real-time data via X integration, strong academic reasoning, and no long-context surcharge.
Its trade-offs: smaller ecosystem than OpenAI/Google, and less independent benchmark coverage. At $3 in / $15 out per million tokens, it sits in the mid price band.
The bottom line for this matchup
Gemini 3.1 Pro and Grok 4 overlap enough that the right pick depends on your specific job. Grok 4 costs less per token; and each leads in its own area — Gemini 3.1 Pro for largest mainstream production context (2m), Grok 4 for 2m production context window. Rather than crowning one, run the same hard task through both once and let the results decide.
Frequently asked questions
Is Gemini 3.1 Pro or Grok 4 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, Gemini 3.1 Pro leans toward largest mainstream production context (2m) while Grok 4 leans toward 2m production context window, and that positioning usually predicts which feels better on your codebase.
Which is cheaper, Gemini 3.1 Pro or Grok 4?
Grok 4 is cheaper — $12/$18 per 1M tokens vs $3/$15 per 1M tokens, roughly 4× apart on input.
Which has the bigger context window?
Both advertise 2M (~3,000 pages). Remember advertised ≠ usable: recall typically degrades before the ceiling.
Can I use both Gemini 3.1 Pro and Grok 4 together?
Yes — a multi-model platform like LumiChats gives you Gemini 3.1 Pro, Grok 4 and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.
Which is newer, Gemini 3.1 Pro or Grok 4?
Gemini 3.1 Pro — released February 2026, about 7 months after Grok 4.
Gemini 3.1 Pro vs Grok 4
Google · US | xAI · US · Updated June 2026
Quick verdict
Pick Gemini 3.1 Pro for largest mainstream production context (2m) or long video and document analysis. Pick Grok 4 for 2m production context window or real-time data via x integration. On a tight budget at scale, Grok 4 is the value pick.
Gemini 3.1 Pro (Google) and Grok 4 (xAI) are two of the models people most often weigh against each other in 2026. Gemini 3.1 Pro is a 2M-token multimodal workhorse — huge breadth, but recall fades deep in the window. Grok 4 is xAI's 2M-context model with live data access and strong reasoning chops. Their biggest split is price, and the breakdown below shows exactly how that plays out for your workload.
Key differences at a glance
▸Price: Grok 4 is about 4× cheaper on input ($3/$15 per 1M tokens vs $12/$18 per 1M tokens) — meaningful once you are processing millions of tokens a month.
▸Context window: both advertise 2M (~3,000 pages). Tie on paper — test on your own long inputs, since usable recall varies by model.
▸Recency: Gemini 3.1 Pro is the newer model by about 7 months (released February 2026), usually meaning fresher training data and capabilities.
Side-by-side specs
Spec
Gemini 3.1 Pro
Grok 4
Provider
Google (US)
xAI (US)
Released
February 2026
2025
Context window
2M (~3,000 pages)
2M (~3,000 pages)
Price (in/out)
$12/$18 per 1M tokens
$3/$15 per 1M tokens
Open weight?
No — API only
No — API only
Modalities
text, image, audio, video, code
text, image, code
SWE-Bench Verified
Not published
Not published
MRCR v2 @ 1M
26.3%
Not published
Who wins what
Largest mainstream production context (2M)
Gemini 3.1 Pro
A core design strength of Gemini 3.1 Pro.
Long video and document analysis
Gemini 3.1 Pro
A core design strength of Gemini 3.1 Pro.
Agentic reasoning (high ARC-AGI-2)
Gemini 3.1 Pro
A core design strength of Gemini 3.1 Pro.
2M production context window
Grok 4
A core design strength of Grok 4.
Real-time data via X integration
Grok 4
A core design strength of Grok 4.
Strong academic reasoning
Grok 4
A core design strength of Grok 4.
Lowest cost at scale
Grok 4
At $3/$15 per 1M tokens, it is the cheaper of the two — the gap dominates the bill on high-volume workloads.
Which should you pick?
A cost-sensitive startup shipping high volume
→ Grok 4
At $3/$15 per 1M tokens it undercuts Gemini 3.1 Pro, and on millions of tokens that margin decides the monthly bill.
Anyone whose priority is largest mainstream production context (2m)
→ Gemini 3.1 Pro
It is specifically built for that.
Anyone whose priority is 2m production context window
→ Grok 4
That is its strongest area.
Gemini 3.1 Pro: where it fits
A 2M-token multimodal workhorse — huge breadth, but recall fades deep in the window. Released February 2026 by Google, it is built for largest mainstream production context (2M), long video and document analysis, agentic reasoning (high ARC-AGI-2), and multimodal understanding.
Its trade-offs are real: long-context recall drops sharply past 256K, and premium price per token. At $12 in / $18 out per million tokens, it sits in the premium price band.
Grok 4: where it fits
XAI's 2M-context model with live data access and strong reasoning chops. Released 2025 by xAI, it is built for 2M production context window, real-time data via X integration, strong academic reasoning, and no long-context surcharge.
Its trade-offs: smaller ecosystem than OpenAI/Google, and less independent benchmark coverage. At $3 in / $15 out per million tokens, it sits in the mid price band.
The bottom line for this matchup
Gemini 3.1 Pro and Grok 4 overlap enough that the right pick depends on your specific job. Grok 4 costs less per token; and each leads in its own area — Gemini 3.1 Pro for largest mainstream production context (2m), Grok 4 for 2m production context window. Rather than crowning one, run the same hard task through both once and let the results decide.
Want both Gemini 3.1 Pro and Grok 4 without two subscriptions? LumiChats gives you these plus 40+ models under one ₹69/day pass (about $1/day) — draft with one, cross-check with the other.
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, Gemini 3.1 Pro leans toward largest mainstream production context (2m) while Grok 4 leans toward 2m production context window, and that positioning usually predicts which feels better on your codebase.
Which is cheaper, Gemini 3.1 Pro or Grok 4?
Grok 4 is cheaper — $12/$18 per 1M tokens vs $3/$15 per 1M tokens, roughly 4× apart on input.
Which has the bigger context window?
Both advertise 2M (~3,000 pages). Remember advertised ≠ usable: recall typically degrades before the ceiling.
Can I use both Gemini 3.1 Pro and Grok 4 together?
Yes — a multi-model platform like LumiChats gives you Gemini 3.1 Pro, Grok 4 and 40+ others under one ₹69/day pass (about $1/day), so you can draft with one and cross-check with the other instead of buying two subscriptions.
Which is newer, Gemini 3.1 Pro or Grok 4?
Gemini 3.1 Pro — released February 2026, about 7 months after Grok 4.
Specifications and benchmarks reflect publicly reported figures as of June 2026 and may change as providers release updates. Always verify on your own workload.