Gemini 2.5 Pro vs Grok 4.3

Name: Gemini 2.5 Pro
Author: Google DeepMind

Gemini 2.5 Pro (2025) and Grok 4.3 (2026) are frontier-tier reasoning models from Google DeepMind and xAI. Gemini 2.5 Pro ships a 1m-token context window, while Grok 4.3 ships a 1m-token context window. On Google-Proof Q&A, Grok 4.3 leads by 3.7 pts. This comparison covers specs, pricing, API access, capabilities, benchmarks, input and output token costs, and production fit for coding and agent workloads.

Pick Grok 4.3 for reasoning; Gemini 2.5 Pro is better when coding workflow support matters more.

Decision scorecard

Local evidence first

Signal	Gemini 2.5 Pro	Grok 4.3	How to read it
Best for	reasoning-heavy apps, multimodal apps, and tool-calling agents	reasoning-heavy apps, multimodal apps, and tool-calling agents	Use-case synthesis from product type, capability flags, context, and provider data.
Decision fit	Coding, RAG, and Agents	RAG, Agents, and Long context	Primary workload tags from local decision data.
Context window	1m	1m	Higher is better when prompts, retrieval chunks, or transcripts are large.
Cheapest output	$10/1M tokens	$2.50/1M tokens	Cheapest tracked provider route; verify your exact region and tier.
Provider routes	4 tracked	4 tracked	Broader coverage can reduce vendor lock-in and fallback risk.
Shared benchmarks	1 shared	Google-Proof Q&A leader	Visible benchmark lead is 3.7 points on Google-Proof Q&A.

Decision tradeoffs

Choose Gemini 2.5 Pro when...

Gemini 2.5 Pro uniquely exposes Code execution in local model data.
Local decision data tags Gemini 2.5 Pro for Coding, RAG, and Agents.

Choose Grok 4.3 when...

Grok 4.3 holds a shared-benchmark lead on Google-Proof Q&A, ahead by 3.7 points.
Grok 4.3 has the lower cheapest tracked output price at $2.50/1M tokens.
Local decision data tags Grok 4.3 for RAG, Agents, and Long context.

Monthly cost at traffic

Estimate token spend from the cheapest tracked input and output route or tier on this page.

Lower estimate Grok 4.3

Requests / monthInput tokens / requestOutput tokens / request

Gemini 2.5 Pro

$3,500

Cheapest tracked route/tier: Google AI Studio <=200K tokens

Grok 4.3

$1,625

Cheapest tracked route/tier: xAI Console

Estimated monthly gap: $1,875. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.

Switch friction

Gemini 2.5 Pro -> Grok 4.3

Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
Grok 4.3 is $7.50/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
Check replacement coverage for Code execution before moving production traffic.

Grok 4.3 -> Gemini 2.5 Pro

Provider overlap exists on OpenRouter and Vercel AI Gateway; start route-level A/B tests there.
Gemini 2.5 Pro is $7.50/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
Gemini 2.5 Pro adds Code execution in local capability data.

Specs

Specification	Gemini 2.5 Pro Google DeepMind	Grok 4.3 xAI
Released	2025-06-17	2026-05-06
Context window	1m	1m
Parameters	—	~0.5T
Architecture	Decoder Only	-
License	Proprietary	Proprietary
Openness	Proprietary	Proprietary
Commercial use	Commercial use with conditions	Commercial use with conditions
Knowledge cutoff	2025-01	2024-11

Pricing and availability

Pricing attribute	Gemini 2.5 Pro	Grok 4.3
Input price	<=200K tokens $1.25/1M tokens Standard Gemini 2.5 Pro pricing for prompts up to 200K tokens. >200K tokens $2.50/1M tokens Higher Gemini 2.5 Pro tier for prompts above 200K tokens.	0-200,001t $1.25/1M tokens 200,001t+ $2.50/1M tokens
Output price	<=200K tokens $10/1M tokens Standard Gemini 2.5 Pro pricing for prompts up to 200K tokens. >200K tokens $15/1M tokens Higher Gemini 2.5 Pro tier for prompts above 200K tokens.	0-200,001t $2.50/1M tokens 200,001t+ $5/1M tokens
Providers	Google AI Studio GCP Vertex AI OpenRouter Vercel AI Gateway	xAI Console OpenRouter Microsoft Foundry Vercel AI Gateway

Capabilities

Capability	Gemini 2.5 Pro	Grok 4.3
Vision	Yes	Yes
Multimodal	Yes	Yes
Reasoning	Yes	Yes
Function calling	Yes	Yes
Tool use	Yes	Yes
Structured outputs	Yes	Yes
Code execution	Yes	No
IDE integration	No	No
Computer use	No	No
Parallel agents	No	No

Benchmarks

Benchmark	Gemini 2.5 Pro	Grok 4.3
Google-Proof Q&A	86.4	90.1

Deep dive

On shared benchmark coverage, Google-Proof Q&A has Gemini 2.5 Pro at 86.4 and Grok 4.3 at 90.1, with Grok 4.3 ahead by 3.7 points. The largest visible gap is 3.7 points on Google-Proof Q&A, which matters most when that benchmark mirrors your workload. Treat isolated benchmark wins as directional, because provider routing, prompt style, and tool access can move real application results.

The capability footprint differs most on code execution: Gemini 2.5 Pro. Both models share vision, multimodal input, reasoning mode, and function calling, so the practical split is not just feature count. Use those differences to decide whether the page is about raw model quality, agentic coding support, multimodal ingestion, or predictable structured API behavior.

For cost, Gemini 2.5 Pro lists tiered pricing: <=200K tokens is $1.25/1M input and $10/1M output; >200K tokens is $2.50/1M input and $15/1M output, while Grok 4.3 lists tiered pricing: 0-200,001t is $1.25/1M input and $2.50/1M output; 200,001t+ is $2.50/1M input and $5/1M output. A 70/30 input-output blend puts Grok 4.3 lower by about $2.25 per million blended tokens. For tiered rows, this cheapest-track view can understate interactive or fast-lane spend, so compare the tier you will actually use. Availability is 4 providers versus 4, so concentration risk also matters.

Choose Gemini 2.5 Pro when coding workflow support are central to the workload. Choose Grok 4.3 when vision-heavy evaluation are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship.

FAQ

Which has a larger context window, Gemini 2.5 Pro or Grok 4.3?

Gemini 2.5 Pro supports 1m tokens, while Grok 4.3 supports 1m tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.

Which is cheaper, Gemini 2.5 Pro or Grok 4.3?

Gemini 2.5 Pro lists tiered pricing: <=200K tokens is $1.25/1M input and $10/1M output; >200K tokens is $2.50/1M input and $15/1M output. Grok 4.3 lists tiered pricing: 0-200,001t is $1.25/1M input and $2.50/1M output; 200,001t+ is $2.50/1M input and $5/1M output. Compare the tier you will actually use; cheap async pricing can overstate savings for interactive workflows. Provider discounts or batch pricing can still change the final bill.

Is Gemini 2.5 Pro or Grok 4.3 open source?

Gemini 2.5 Pro is listed under Proprietary. Grok 4.3 is listed under Proprietary. License labels affect whether you can self-host, redistribute weights, or rely only on hosted APIs, so confirm the upstream license before deployment.

Which is better for vision, Gemini 2.5 Pro or Grok 4.3?

Both Gemini 2.5 Pro and Grok 4.3 expose vision. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface. Use this as a quick comparison signal, then confirm the provider-specific limits before committing to production.

Which is better for multimodal input, Gemini 2.5 Pro or Grok 4.3?

Both Gemini 2.5 Pro and Grok 4.3 expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.

Where can I run Gemini 2.5 Pro and Grok 4.3?

Gemini 2.5 Pro is available on Google AI Studio, GCP Vertex AI, OpenRouter, and Vercel AI Gateway. Grok 4.3 is available on xAI Console, OpenRouter, Microsoft Foundry, and Vercel AI Gateway. Provider coverage can affect latency, region availability, compliance posture, and fallback options.

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Last reviewed: 2026-06-15. Data sourced from public model cards and provider documentation.

Both models

Gemini 2.5 Pro Grok 4.3