Gemini 2.5 Pro vs Grok 4
Gemini 2.5 Pro and Grok 4 were mid-2025 frontier reasoning models, but they are no longer equal production choices. Gemini 2.5 Pro remains Google's stable GA flagship with a 1M-token context window, multimodal input, and strong coding rows. Grok 4 is retired; use this page for historical comparison and route new xAI evaluations toward Grok 4.3.
Pick Gemini 2.5 Pro for long-context coding assistance, multimodal analysis, and any production comparison against the retired Grok 4 API. If xAI is still on your shortlist, test Grok 4.3 instead: it replaces Grok 4, restores a 1M-token context window, and keeps xAI's much lower $2.50/M output price on the tracked direct route.
Decision scorecard
Local evidence first| Signal | Gemini 2.5 Pro | Grok 4 |
|---|---|---|
| Best for | reasoning-heavy apps, multimodal apps, and tool-calling agents | reasoning-heavy apps, multimodal apps, and tool-calling agents |
| Decision fit | Coding, RAG, and Agents | Coding, RAG, and Agents |
| Context window | 1m | 256k |
| Cheapest output | $10/1M tokens | $2.50/1M tokens |
| Provider routes | 4 tracked | 4 tracked |
| Shared benchmarks | 7 shared | MMLU PRO leader |
Decision tradeoffs
- Gemini 2.5 Pro holds a shared-benchmark lead on Aider Polyglot, ahead by 3.5 points.
- Gemini 2.5 Pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Local decision data tags Gemini 2.5 Pro for Coding, RAG, and Agents.
- Grok 4 holds a shared-benchmark lead on MMLU PRO, ahead by 0.8 points.
- Grok 4 has the lower cheapest tracked output price at $2.50/1M tokens.
- Local decision data tags Grok 4 for Coding, RAG, and Agents.
Monthly cost at traffic
Estimate token spend from the cheapest tracked input and output route or tier on this page.
Gemini 2.5 Pro
$3,500
Cheapest tracked route/tier: Google AI Studio <=200K tokens
Grok 4
$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
- Provider overlap exists on OpenRouter; start route-level A/B tests there.
- Grok 4 is $7.50/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Provider overlap exists on OpenRouter; 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.
Specs
| Specification | ||
|---|---|---|
| Released | 2025-06-17 | 2025-07-09 |
| Context window | 1m | 256k |
| Parameters | — | — |
| Architecture | Decoder Only | Decoder Only |
| License | Proprietary | Proprietary |
| Openness | Proprietary | Proprietary |
| Weights | Not released | Not released |
| Code | Unknown | Unknown |
| Commercial use | Commercial use: conditional | Commercial use: conditional |
| Knowledge cutoff | 2025-01 | - |
Pricing and availability
| Pricing attribute | Gemini 2.5 Pro | Grok 4 |
|---|---|---|
| Input price |
| $1.25/1M tokens |
| Output price |
| $2.50/1M tokens |
| Providers |
Capabilities
| Capability | Gemini 2.5 Pro | Grok 4 |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | Yes | Yes |
| Function calling | Yes | Yes |
| Tool use | Yes | Yes |
| Structured outputs | Yes | Yes |
| Code execution | Yes | Yes |
| IDE integration | No | No |
| Computer use | No | No |
| Parallel agents | No | No |
Benchmarks
| Benchmark | Gemini 2.5 Pro | Grok 4 |
|---|---|---|
| MMLU PRO | 86.2 | 87.0 |
| SWE-bench Verified | 63.8 | 76.7 |
| Google-Proof Q&A | 86.4 | 87.5 |
| AIME 2025 | 86.7 | 91.7 |
| LiveCodeBench | 75.6 | 79.0 |
| Humanity's Last Exam | 18.8 | 25.4 |
| Aider Polyglot | 83.1 | 79.6 |
Deep dive
The lifecycle caveat comes first. Grok 4 has an xAI API retirement date of May 15, 2026, so the practical buyer question is not whether to start a new Grok 4 integration. Keep this page indexable for the existing search demand, but treat the xAI production path as Grok 4.3.
The cleanest coding signal favors Gemini. On Aider Polyglot, Gemini 2.5 Pro scores 83.1% versus Grok 4 at 79.6%, using the same aider.chat harness on 225 Exercism exercises across six languages. That is the most apples-to-apples coding row in the handoff.
Reasoning evidence is useful but not seed-ready for a new Grok GPQA row. Gemini 2.5 Pro has a sourced GPQA Diamond row at 86.4%. The handoff reports an 88.0% Grok 4 launch claim, but the primary xAI source was unavailable during research and the handoff asks for verification before seeding, so this page keeps that as copy context rather than a modelBenchmark row.
Context and modality are the decisive production differences. Gemini 2.5 Pro supports about 1M tokens and accepts text, image, audio, and video input. Original Grok 4 is tracked at 256K context with text and image input, which makes Gemini the safer fit for codebase-scale review, long documents, media analysis, and retrieval packs.
Cost changes once you compare against the active successor. Gemini 2.5 Pro's standard Google route is $1.25/M input and $10/M output up to 200K tokens. Grok 4.3's tracked xAI route is $1.25/M input and $2.50/M output, so teams that can validate xAI quality on their own prompts should compare Gemini directly with Grok 4.3 before committing.
FAQ
Is Grok 4 still available?
No. Grok 4 has an xAI API retirement date of May 15, 2026. LLMReference keeps this comparison for search and migration context, but new xAI integrations should test Grok 4.3 instead.
Which model is better for coding, Gemini 2.5 Pro or Grok 4?
Gemini 2.5 Pro has the cleaner comparable coding win in this handoff: 83.1% on Aider Polyglot versus 79.6% for Grok 4 using the same aider.chat benchmark. Grok 4 has a stronger SWE-bench Verified number in the seed, but the handoff notes that the agent scaffolds differ, so that row should not be read as a direct head-to-head.
What is the context window difference?
Gemini 2.5 Pro supports about 1M tokens. Original Grok 4 is tracked at 256K tokens, while Grok 4.3, the current successor, also reaches a 1M-token context window.
Which is cheaper?
Gemini 2.5 Pro lists $1.25/M input and $10/M output on the standard Google route for prompts up to 200K tokens. Grok 4 is retired, but Grok 4.3's tracked xAI route lists $1.25/M input and $2.50/M output, making the current xAI successor much cheaper on output tokens.
Why is the Grok 4 GPQA score not added as a seed row?
The handoff reports an 88.0% Grok 4 GPQA Diamond launch claim, but its primary xAI source was unavailable and the handoff asks for verification before seeding. This integration therefore leaves the row out instead of promoting a medium-confidence secondary-source score into modelBenchmark.json.
Continue comparing
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Last reviewed: 2026-07-10. Data sourced from public model cards and provider documentation.