What Hardware Do You Need for Microsoft Phi-4?

By LLM Hardware team · Methodology ·

AI drafted the Phi-4 size matrix from Microsoft's model cards. VRAM numbers here come from the methodology page formula.

Key facts

Phi-4 14B Q4
about 10.4 GB by our formula (Ollama's phi4 file is 9.1 GB)
Comfortable card
12–16 GB
Checked
2026-10-13
Author
LLM Hardware team

Checked 2026-10-13. Author: LLM Hardware team. This site does not store or show Amazon prices. Check current price on Amazon.

Citeable facts

Key fact: Phi-4 14B at Q4 needs 10.4 GB. An 8 GB GPU does not fit it. A 12 GB GPU does. Q8 is 18.8 GB and misses 16 GB.

How we got it: 14 × 0.5 × 1.2 + 2 = 10.4. 14 × 1.2 + 2 = 18.8. Ollama library on 11 October 2026 still listed phi4, phi4:14b, and phi4-mini.

Checked:

Key fact: Phi-4-mini at 3.8B needs 4.3 GB at Q4. It fits 8 GB and does not fit a 4 GB GPU.

How we got it: 3.8 × 0.5 × 1.2 + 2 = 4.3. Hugging Face microsoft/Phi-4-mini-instruct.

Checked:

Methodology — parameter math, quantization bytes, and the source list.

Updated 24 October 2026 · Phi-4 14B & Phi-4-mini 3.8B · VRAM requirements · Consumer GPU guide · Ollama setup

Phi-4, released by Microsoft in December 2024, is a 14B model. At Q4 our VRAM formula is 14 × 0.6 + 2 = 10.4 GB, so it needs a 12 GB GPU. An 8 GB GPU does not fit it. Q8 is 18.8 GB and needs 24 GB. Phi-4-mini (3.8B) at Q4 is 4.3 GB and fits an 8 GB GPU. Run ollama run phi4 or ollama run phi4-mini. Both tags were on the Ollama library on 11 October 2026. In LM Studio, pick the Q4_K_M GGUF of the same size.

What is Phi-4?

Phi-4 is Microsoft's flagship small language model, trained on high-quality synthetic "textbook" data rather than raw web text. This gives it exceptional reasoning and coding performance far beyond what its 14B parameter count would suggest.

Phi-4 VRAM Requirements by Model Size

The MSI RTX 4060 Ti 16 GB (B0CBK7BRL9) fits phi4 at Q4 (10.4 GB) and does not fit Q8 (18.8 GB). Links to Amazon are affiliate links. Check current price on Amazon.

MSI RTX 4060 Ti 16 GB on Amazon

VRAM is estimated using params × bytes_per_param × 1.2 + 2. Q4 is params_B × 0.6 + 2. Q8 is params_B × 1.2 + 2. FP16 is params_B × 2.4 + 2. Add extra headroom for KV cache when using long context windows.

ModelParamsQ4_K_M VRAMQ8 VRAMFP16 VRAMMin GPU
Phi-4-mini 3.8B 4.3 GB 6.6 GB 11.1 GB 8 GB GPU
Phi-4 14B 10.4 GB 18.8 GB 35.6 GB 12 GB GPU

Phi-4 14B at Q4 is 10.4 GB, so an 8 GB GPU does not fit it. Use the VRAM Calculator for context-length-adjusted estimates and KV cache projections.

Why Phi-4 Punches Above Its Weight

Most 14B models land firmly behind 70B models on hard benchmarks. Phi-4 is the exception. Here is why it performs so far above its size:

Synthetic textbook data

Microsoft trained Phi-4 on carefully curated synthetic data modeled on textbooks and structured problem sets — not raw web crawls. This means fewer low-quality examples and more reasoning signal per token.

Benchmark results

In Microsoft's own table, Phi-4 scores higher than Llama 3.3 70B on GPQA (56.1 vs 49.1), MATH (80.4 vs 66.3) and HumanEval (82.6 vs 78.9), and lower on MMLU (84.8 vs 86.3), MGSM (80.6 vs 89.1), DROP (75.5 vs 90.2) and SimpleQA (3.0 vs 20.9). Microsoft notes that Meta reports higher Llama 3.3 scores on MATH (77) and HumanEval (88).

Coding and math focus

If your use case is code generation, debugging, mathematical reasoning, or structured logic tasks, Phi-4 is one of the best models available regardless of size class.

Trade-off: multilingual

Phi-4 is primarily English-focused. Multilingual performance is noticeably weaker than Qwen3 14B. For multilingual use cases, Qwen3 is the better pick at the same VRAM tier.

What Phi-4 Can You Run on Your GPU?

Find your GPU or Mac below. Each card shows which Phi-4 variants fit, and what does not.

RTX 4060 8GB

Runs:

  • +Phi-4-mini Q4 (4.3 GB)
  • +Phi-4-mini Q8 (6.6 GB)

Does not fit:

  • -Phi-4 14B Q4 (10.4 GB)
  • -Phi-4 14B Q8 (18.8 GB)

An 8 GB card fits phi4-mini. It does not fit phi4 (10.4 GB at Q4). On 11 October 2026 the new buy box for the 4060 listing was not readable. Check current price on Amazon.

Intel Arc B580 12GB

Runs:

  • +Phi-4-mini Q4 (4.3 GB)
  • +Phi-4 14B Q4 (10.4 GB)

Does not fit:

  • -Phi-4 14B Q8 (18.8 GB)
  • -Phi-4 14B FP16 (35.6 GB)

12 GB holds phi4 at Q4 (10.4 GB) with little KV left. It does not hold Q8. Verify the Ollama oneAPI path before you buy Arc for this model. Check current price on Amazon.

RTX 4070 12GB

Runs:

  • +Phi-4-mini Q4 (4.3 GB)
  • +Phi-4 14B Q4 (10.4 GB)

Does not fit:

  • -Phi-4 14B Q8 (18.8 GB)
  • -Phi-4 14B FP16 (35.6 GB)

Same 12 GB ceiling as the Arc B580: phi4 at Q4 fits, Q8 does not. Check current price on Amazon.

RTX 4060 Ti 16GB

Runs:

  • +Phi-4-mini Q4 and Q8
  • +Phi-4 14B Q4 (10.4 GB)

Does not fit:

  • -Phi-4 14B Q8 (18.8 GB)
  • -Phi-4 14B FP16 (35.6 GB)

16 GB fits phi4 at Q4 and does not fit Q8. Check current price on Amazon.

RTX 4070 Ti Super 16GB

Runs:

  • +Phi-4 14B Q4 (10.4 GB)

Does not fit:

  • -Phi-4 14B Q8 (18.8 GB)
  • -Phi-4 14B FP16 (35.6 GB)

Faster than a 4060 Ti, same 16 GB ceiling. phi4 at Q8 still does not fit. No new price was recorded for this SKU on 11 October.

RTX 4080 16GB

Runs:

  • +Phi-4 14B Q4 (10.4 GB)

Does not fit:

  • -Phi-4 14B Q8 (18.8 GB)
  • -Phi-4 14B FP16 (35.6 GB)

Bandwidth does not change the 18.8 GB miss. Check current price on Amazon.

RTX 3090 24GB (used)

Runs:

  • +Phi-4 14B Q4 (10.4 GB)
  • +Phi-4 14B Q8 (18.8 GB)

Does not fit:

  • -Phi-4 14B FP16 (35.6 GB)

24 GB is the first discrete tier that fits phi4 at Q8. Check current price on Amazon.

RTX 4090 24GB

Runs:

  • +Phi-4 14B Q4 (10.4 GB)
  • +Phi-4 14B Q8 (18.8 GB)

Does not fit:

  • -Phi-4 14B FP16 (35.6 GB)

24 GB fits phi4 at Q8. It does not fit FP16. Check current price on Amazon.

RTX 5090 32GB

Runs:

  • +Phi-4 14B Q4 (10.4 GB)
  • +Phi-4 14B Q8 (18.8 GB)

Does not fit:

  • -Phi-4 14B FP16 (35.6 GB)

32 GB fits phi4 at Q8 and does not fit the 35.6 GB FP16 estimate. A 12 GB card already runs the Q4 file. Check current price on Amazon.

Mac mini M4 16GB

Runs:

  • +Phi-4-mini Q4 (4.3 GB)
  • +Phi-4 14B Q4 (10.4 GB), tight after a 4 GB macOS reserve

Does not fit:

  • -Phi-4 14B Q8 (18.8 GB)

Treat usable memory as about 12 GB. phi4 at Q4 is the ceiling and is tight. Q8 does not fit.

Mac mini M4 24GB

Runs:

  • +Phi-4 14B Q4 (10.4 GB)
  • +Phi-4 14B Q8 (18.8 GB), tight after the macOS reserve

Does not fit:

  • -Phi-4 14B FP16 (35.6 GB)

A 24 GB Mac is not a 24 GB GPU. Q8 can load and has little room for a long context. Check current price on Amazon.

Mac mini M4 Pro 48GB

Runs:

  • +Phi-4 14B Q8 (18.8 GB)
  • +Phi-4 14B FP16 (35.6 GB) after a 4 GB macOS reserve

Does not fit:

  • -Nothing in the Phi-4 family misses 48 GB unified

After a 4 GB reserve a 48 GB Mac still holds the 35.6 GB FP16 estimate. No new Amazon price was verified for the 48 GB M4 Pro mini on 11 October.

Inference Speed by Hardware

Token generation speed is bottlenecked by memory bandwidth. The table below shows estimated Q4_K_M token speeds at low batch size. Real-world results vary by driver version, context length, and system load.

HardwareBandwidthPhi-4-mini tok/sPhi-4 14B Q4 tok/sPhi-4 14B Q8 tok/s
RTX 5090 32GB 1,792 GB/s ~400 t/s ~95 t/s ~60 t/s
RTX 4090 24GB 1,008 GB/s ~225 t/s ~55 t/s ~34 t/s
RTX 4070 Ti Super 16GB 672 GB/s ~150 t/s ~37 t/s —
RTX 4080 16GB 720 GB/s ~160 t/s ~39 t/s —
RTX 4060 Ti 16GB 288 GB/s ~64 t/s ~16 t/s —
Intel Arc B580 12GB 456 GB/s ~102 t/s ~25 t/s —
RTX 4060 8GB 272 GB/s ~61 t/s — —
Mac mini M4 Pro 48GB ~273 GB/s ~61 t/s ~15 t/s ~9 t/s
Mac mini M4 24GB ~120 GB/s ~27 t/s ~7 t/s ~4 t/s
Mac mini M4 16GB ~120 GB/s ~27 t/s ~7 t/s —

Speed estimates: tokens/sec ≈ bandwidth (GB/s) / model size in memory (GB). Dash (—) means the model does not fit. An 8 GB GPU does not run phi4 at Q4, and a 16 GB GPU does not run it at Q8.

How to Run Phi-4 Locally

Ollama

ollama run phi4

Easiest option. For Phi-4 14B: ollama run phi4. For Phi-4-mini: ollama run phi4-mini. Both tags were on the Ollama library on 11 October 2026. Ollama defaults to a Q4 file. Use phi4 only when the card has 12 GB. An 8 GB GPU should stay on phi4-mini.

LM Studio

Search "Phi-4" in Discover

GUI-based model browser and chat interface. Search for "Phi-4" in the Discover tab to find Microsoft's official GGUF variants. Lets you select Q4, Q8, or other quantizations from a dropdown. Best for non-technical users on Windows, Mac, or Linux.

Hugging Face + llama.cpp

microsoft/phi-4

Download GGUF files from microsoft/phi-4 or community repos (bartowski, unsloth) on Hugging Face. Run with llama.cpp for maximum control over quantization, GPU layer count, and context length. Use --n-gpu-layers to tune how many layers load onto VRAM.

For step-by-step installation instructions, see the how to run LLMs locally guide. For a comparison of Ollama vs LM Studio, see the Ollama vs LM Studio guide.

Running Phi-4 CPU-Only

No GPU? Phi-4-mini (3.8B) is one of the best CPU-only models available. At Q4_K_M it needs about 4.3 GB of RAM and generates 4–8 tokens per second on a modern CPU — fast enough for practical use.

System RAM needed

Phi-4-mini at Q4: 4.3 GB. Phi-4 14B at Q4: 10.4 GB. For CPU inference, ensure your total system RAM exceeds the model size by at least 2–4 GB to leave room for the OS and context cache.

Speed on CPU

Phi-4-mini: 4–8 tok/s on a modern CPU (Ryzen 7, Core i7). Phi-4 14B on CPU: 1–3 tok/s — usable but slow. For 14B CPU inference, consider 32+ GB RAM and a fast CPU with many cores. Phi-4-mini is the practical CPU choice.

How to run CPU-only

With Ollama: ollama run phi4-mini — it auto-detects if no GPU is available and falls back to CPU. With llama.cpp: use --n-gpu-layers 0 to force CPU-only mode. LM Studio has a CPU mode toggle in settings.

For a detailed guide to CPU-only inference, see the CPU-only LLM inference guide.

Phi-4 14B vs Qwen3 14B vs Gemma 3 12B

All three target the same ~8–12 GB VRAM tier. Here is how they compare for local inference:

Phi-4 14BQwen3 14BGemma 3 12B
VRAM at Q4 10.4 GB 10.4 GB 9.2 GB
Thinking mode No Yes (built-in) No
Coding Excellent Very good Good
Reasoning/math Excellent Very good Good
Multilingual Poor Excellent Good
Creative writing Average Good Good
Best for Coding/math General + multilingual Balanced use

Choose Phi-4 if...

  • +Your primary use case is coding or math
  • +You want the best reasoning-per-VRAM ratio
  • +English-only tasks are your focus
  • +You prefer Microsoft's training approach

Choose Qwen3 14B if...

  • +You need built-in chain-of-thought reasoning
  • +Multilingual tasks are important
  • +You want a general-purpose model
  • +You want thinking mode without extra setup

Choose Gemma 3 12B if...

  • +You want Google-backed architecture
  • +You need balanced multilingual + reasoning
  • +You have 12 GB: Gemma 3 12B at Q4 is 9.2 GB and does not fit 8 GB
  • +You prioritize model diversity across sizes (1B–27B)

Which Hardware Should You Buy for Phi-4?

Entry tier

RTX 4060 8GB

Does not fit phi4 at Q4 (10.4 GB). It does fit phi4-mini (4.3 GB). Keep this card only if you already own it. Check current price on Amazon.

12 GB — best value

Intel Arc B580 12GB

Fits phi4 at Q4 (10.4 GB) and does not fit Q8 (18.8 GB). Verify the Ollama oneAPI path before you buy Arc for this model. Check current price on Amazon.

Mid tier

RTX 4060 Ti 16GB

Fits phi4 at Q4 (10.4 GB) and does not fit Q8 (18.8 GB). Check current price on Amazon.

Used 24 GB

RTX 3090 24GB

Fits phi4 at Q8 (18.8 GB). Does not fit FP16 (35.6 GB). Check current price on Amazon.

High end

RTX 4090 24GB

Fits phi4 at Q8 (18.8 GB) and does not fit FP16 (35.6 GB). A 12 GB card already runs the Q4 file. Check current price on Amazon.

Mac ecosystem

Mac mini M4 16GB

After a 4 GB macOS reserve, phi4 at Q4 (10.4 GB) is tight on 16 GB unified memory. Q8 (18.8 GB) does not fit. A 24 GB Mac holds Q8 and is tight. phi4-mini at 4.3 GB needs more than an 8 GB Mac, which leaves about 4 GB after macOS.

For a full cross-budget GPU comparison, see the best GPU for LLMs guide.

Related Resources

Frequently Asked Questions

Is Phi-4 better than Llama 3.1 8B?

Phi-4 14B is the stronger reasoning and coding model in Microsoft's comparisons with Llama 3.1 8B. The VRAM cost is 10.4 GB at Q4 versus 6.8 GB for the 8B model. Phi-4 needs 12 GB. The 8B model fits 8 GB.

Can an 8GB GPU run Phi-4?

No. 14 × 0.6 + 2 = 10.4 GB, so an RTX 4060 8 GB does not fit phi4. Use a 12 GB card such as the Arc B580, or stay on ollama run phi4-mini (4.3 GB at Q4). Q8 of the 14B model is 18.8 GB and misses 16 GB.

How does Phi-4 compare to Qwen3 14B?

Both are 14 × 0.6 + 2 = 10.4 GB at Q4. Both fit 12 GB and miss 8 GB. Phi-4 leads on coding, math, and logical reasoning. Qwen3 14B has built-in thinking mode and is the stronger multilingual pick.

Can I run Phi-4 on a Mac?

Yes. Phi-4 runs well on Apple Silicon via Ollama or LM Studio. After about 4 GB for macOS, a 16 GB Mac holds Phi-4 at Q4 (10.4 GB) with about 1.6 GB to spare, so keep the context short. A 24 GB Mac holds Q8 (18.8 GB) with about 1.2 GB to spare. Phi-4-mini at Q4 (4.3 GB) fits a 16 GB Mac; on an 8 GB Mac it does not fit after the reserve.

How much VRAM does Phi-4 need?

Phi-4 (14B) at Q4 is 10.4 GB. Q8 is 18.8 GB. FP16 is 35.6 GB. Phi-4-mini (3.8B) at Q4 is 4.3 GB and fits 8 GB. The 14B model needs 12 GB at Q4. An 8 GB GPU does not fit it. Q8 needs 24 GB. FP16 does not fit 32 GB.

What is Phi-4-mini and how does it differ from Phi-4?

Phi-4-mini is a 3.8B parameter model from Microsoft that needs 4.3 GB of VRAM at Q4_K_M, so it fits an 8 GB GPU but not a 4 GB one. It is designed for edge devices, CPU-only inference, and low-memory GPUs. While smaller than Phi-4 (14B), it still outperforms many older 7B models on coding and reasoning. Use Phi-4-mini when you have an 8 GB GPU, run CPU-only, or need fast inference on a constrained device. Use Phi-4 14B when you have a 12 GB+ GPU and want maximum quality.

Check VRAM requirements for Phi-4, or compare hardware options.

Related Guides

Sources & methodology

VRAM figures on this page come from the site’s VRAM formula and model cards. The sitewide formula and the full source list are on the methodology page. For this guide we used:

Spot a number that does not match the linked source? Contact us and we will update the guide.