GPT-5 Pro vs Grok 4
GPT-5 Pro (2025) and Grok 4 (2025) are frontier reasoning models from OpenAI and xAI. GPT-5 Pro ships a 400k-token context window, while Grok 4 ships a 256k-token context window. On pricing, Grok 4 costs $1.25/1M input tokens versus $15/1M for the alternative. This comparison covers specs, pricing, capabilities, benchmarks, provider availability, and production fit. It focuses on practical selection signals rather than broad model-family marketing.
Grok 4 is ~1100% cheaper at $1.25/1M; pay for GPT-5 Pro only for coding workflow support.
Decision scorecard
Local evidence first| Signal | GPT-5 Pro | Grok 4 |
|---|---|---|
| Best for | 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 | 400k | 256k |
| Cheapest output | $120/1M tokens | $2.50/1M tokens |
| Provider routes | 1 tracked | 4 tracked |
| Shared benchmarks | 0 rows | 0 rows |
Decision tradeoffs
- GPT-5 Pro has the larger context window for long prompts, retrieval packs, or transcript analysis.
- Local decision data tags GPT-5 Pro for Coding, RAG, and Agents.
- Grok 4 has the lower cheapest tracked output price at $2.50/1M tokens.
- Grok 4 has broader tracked provider coverage for fallback and procurement flexibility.
- Grok 4 uniquely exposes Reasoning in local model data.
- 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.
GPT-5 Pro
$42,000
Cheapest tracked route/tier: Vercel AI Gateway
Grok 4
$1,625
Cheapest tracked route/tier: xAI Console
Estimated monthly gap: $40,375. Batch, cache, alternate speed tiers, and negotiated pricing are excluded from this local estimate.
Switch friction
- No overlapping tracked provider route is sourced for GPT-5 Pro and Grok 4; plan for SDK, billing, or endpoint changes.
- Grok 4 is $118/1M tokens lower on cheapest tracked output pricing before cache, batch, or negotiated discounts.
- Grok 4 adds Reasoning in local capability data.
- No overlapping tracked provider route is sourced for Grok 4 and GPT-5 Pro; plan for SDK, billing, or endpoint changes.
- GPT-5 Pro is $118/1M tokens higher on cheapest tracked output pricing, so quality gains need to justify the spend.
- Check replacement coverage for Reasoning before moving production traffic.
Specs
Pricing and availability
| Pricing attribute | GPT-5 Pro | Grok 4 |
|---|---|---|
| Input price | $15/1M tokens | $1.25/1M tokens |
| Output price | $120/1M tokens | $2.50/1M tokens |
| Providers |
Capabilities
| Capability | GPT-5 Pro | Grok 4 |
|---|---|---|
| Vision | Yes | Yes |
| Multimodal | Yes | Yes |
| Reasoning | No | 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
No shared benchmark rows are currently sourced for this pair.
Deep dive
The capability footprint differs most on reasoning mode: Grok 4. Both models share vision, multimodal input, function calling, and tool use, 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, GPT-5 Pro lists $15/1M input and $120/1M output tokens on the cheapest tracked provider, while Grok 4 lists $1.25/1M input and $2.50/1M output tokens on the cheapest tracked provider. A 70/30 input-output blend puts Grok 4 lower by about $44.88 per million blended tokens. Availability is 1 providers versus 4, so concentration risk also matters.
Choose GPT-5 Pro when coding workflow support and larger context windows are central to the workload. Choose Grok 4 when coding workflow support, lower input-token cost, and broader provider choice are more important. For production, rerun your own prompts through the exact provider, region, and tool stack you plan to ship. This keeps the decision grounded in measurable tradeoffs instead of brand-level assumptions. It also helps separate model capability from provider packaging, which can change cost and latency.
FAQ
Which has a larger context window, GPT-5 Pro or Grok 4?
GPT-5 Pro supports 400k tokens, while Grok 4 supports 256k tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Which is cheaper, GPT-5 Pro or Grok 4?
Grok 4 is cheaper on tracked token pricing. GPT-5 Pro costs $15/1M input and $120/1M output tokens. Grok 4 costs $1.25/1M input and $2.50/1M output tokens. Provider discounts or batch pricing can still change the final bill.
Is GPT-5 Pro or Grok 4 open source?
GPT-5 Pro is listed under Proprietary. Grok 4 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, GPT-5 Pro or Grok 4?
Both GPT-5 Pro and Grok 4 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, GPT-5 Pro or Grok 4?
Both GPT-5 Pro and Grok 4 expose multimodal input. 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.
Where can I run GPT-5 Pro and Grok 4?
GPT-5 Pro is available on Vercel AI Gateway. Grok 4 is available on Microsoft Foundry, OpenRouter, Replicate API, and xAI Console. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-05-22. Data sourced from public model cards and provider documentation.