Grok 4.3 Beta vs Phi-4 Reasoning Vision 15B
Grok 4.3 Beta (2026) and Phi-4 Reasoning Vision 15B (2026) are frontier reasoning models from xAI and Microsoft Research. Grok 4.3 Beta ships a 2M-token context window, while Phi-4 Reasoning Vision 15B ships a not-yet-sourced context window. 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 4.3 Beta is safer overall; choose Phi-4 Reasoning Vision 15B when provider fit matters.
Specs
| Released | 2026-04-17 | 2026-03-12 |
| Context window | 2M | — |
| Parameters | ~0.5T | 15B |
| Architecture | - | - |
| License | Proprietary | Microsoft Research |
| Knowledge cutoff | - | - |
Pricing and availability
| Grok 4.3 Beta | Phi-4 Reasoning Vision 15B | |
|---|---|---|
| Input price | - | - |
| Output price | - | - |
| Providers | - | - |
Pricing not yet sourced for either model.
Capabilities
| Grok 4.3 Beta | Phi-4 Reasoning Vision 15B | |
|---|---|---|
| Vision | ||
| Multimodal | ||
| Reasoning | ||
| Function calling | ||
| Tool use | ||
| Structured outputs | ||
| Code execution |
Benchmarks
No shared benchmark rows are currently sourced for this pair.
Deep dive
The capability footprint differs most on vision: Grok 4.3 Beta, reasoning mode: Grok 4.3 Beta, function calling: Grok 4.3 Beta, tool use: Grok 4.3 Beta, and structured outputs: Grok 4.3 Beta. Both models share multimodal input, 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.
Pricing coverage is uneven: Grok 4.3 Beta has no token price sourced yet and Phi-4 Reasoning Vision 15B has no token price sourced yet. Provider availability is 0 tracked routes versus 0. Treat unknown pricing as an integration gap, then verify the route you will actually call before estimating production spend.
Choose Grok 4.3 Beta when reasoning depth are central to the workload. Choose Phi-4 Reasoning Vision 15B when provider fit 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
Is Grok 4.3 Beta or Phi-4 Reasoning Vision 15B open source?
Grok 4.3 Beta is listed under Proprietary. Phi-4 Reasoning Vision 15B is listed under Microsoft Research. 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, Grok 4.3 Beta or Phi-4 Reasoning Vision 15B?
Grok 4.3 Beta has the clearer documented vision signal in this comparison. If vision is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for multimodal input, Grok 4.3 Beta or Phi-4 Reasoning Vision 15B?
Both Grok 4.3 Beta and Phi-4 Reasoning Vision 15B expose multimodal input. The better choice depends on benchmark fit, context budget, pricing, and whether your provider route exposes the same capability surface.
Which is better for reasoning mode, Grok 4.3 Beta or Phi-4 Reasoning Vision 15B?
Grok 4.3 Beta has the clearer documented reasoning mode signal in this comparison. If reasoning mode is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for function calling, Grok 4.3 Beta or Phi-4 Reasoning Vision 15B?
Grok 4.3 Beta has the clearer documented function calling signal in this comparison. If function calling is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
When should I pick Grok 4.3 Beta over Phi-4 Reasoning Vision 15B?
Grok 4.3 Beta is safer overall; choose Phi-4 Reasoning Vision 15B when provider fit matters. If your workload also depends on reasoning depth, start with Grok 4.3 Beta; if it depends on provider fit, run the same evaluation with Phi-4 Reasoning Vision 15B.
Continue comparing
Last reviewed: 2026-04-25. Data sourced from public model cards and provider documentation.