Grok 4.3 Beta vs Phi 3.5 Mini Instruct
Grok 4.3 Beta (2026) and Phi 3.5 Mini Instruct (2024) are frontier reasoning models from xAI and Microsoft Research. Grok 4.3 Beta ships a 2M-token context window, while Phi 3.5 Mini Instruct ships a 128K-token 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 fits 16x more tokens; pick it for long-context work and Phi 3.5 Mini Instruct for tighter calls.
Specs
| Released | 2026-04-17 | 2024-08-20 |
| Context window | 2M | 128K |
| Parameters | ~0.5T | 3.8B |
| Architecture | - | decoder only |
| License | Proprietary | MIT |
| Knowledge cutoff | - | - |
Pricing and availability
| Grok 4.3 Beta | Phi 3.5 Mini Instruct | |
|---|---|---|
| Input price | - | $0.9/1M tokens |
| Output price | - | $0.9/1M tokens |
| Providers | - |
Capabilities
| Grok 4.3 Beta | Phi 3.5 Mini Instruct | |
|---|---|---|
| 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, multimodal input: 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 the core language-model surface, 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 3.5 Mini Instruct has $0.9/1M input tokens. Provider availability is 0 tracked routes versus 2. 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 and larger context windows are central to the workload. Choose Phi 3.5 Mini Instruct when provider fit 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.
FAQ
Which has a larger context window, Grok 4.3 Beta or Phi 3.5 Mini Instruct?
Grok 4.3 Beta supports 2M tokens, while Phi 3.5 Mini Instruct supports 128K tokens. That gap matters most for long documents, large codebases, retrieval-heavy agents, and conversations where earlier context must remain visible.
Is Grok 4.3 Beta or Phi 3.5 Mini Instruct open source?
Grok 4.3 Beta is listed under Proprietary. Phi 3.5 Mini Instruct is listed under MIT. 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 3.5 Mini Instruct?
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 3.5 Mini Instruct?
Grok 4.3 Beta has the clearer documented multimodal input signal in this comparison. If multimodal input is mission-critical, validate it against the provider endpoint because model-level support and API-level exposure can differ.
Which is better for reasoning mode, Grok 4.3 Beta or Phi 3.5 Mini Instruct?
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.
Where can I run Grok 4.3 Beta and Phi 3.5 Mini Instruct?
Grok 4.3 Beta is available on the tracked providers still being sourced. Phi 3.5 Mini Instruct is available on Fireworks AI and NVIDIA NIM. Provider coverage can affect latency, region availability, compliance posture, and fallback options.
Continue comparing
Last reviewed: 2026-04-25. Data sourced from public model cards and provider documentation.