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What Is VRAM and How Much Do You Need for Local LLMs?

VRAM needed to run LLMs locally by model size and quantization, from 4B to 671B, with the cheapest GPU or system that fits each.

Last updated21 Oct 2026
Fact-checked21 Oct 2026
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What is VRAM? It is the memory on your graphics card; the model must fit in it to run at full speed (full explainer: what is VRAM).

Short answer: at 4-bit quantization, plan on roughly 0.61 GB per billion parameters (Q4_K_M ≈ 4.89 bits/weight) plus a few GB for context. 8B models fit 8 GB cards tightly; 30B-class models want 24 GB; 70B models need 48 GB or a 128 GB unified-memory system.

ModelParams (total / active)Est. memory, Q4 @ 8k ctxEst. memory, Q8 @ 8k ctxCheapest fit in our data (Q4)
Qwen3 4B4.0B / 4.0B4.9 GB6.8 GBGeForce RTX 5060 ($299, GPU launch MSRP)
Llama 3.1 8B8.03B / 8.03B7.0 GB10.6 GBGeForce RTX 5060 ($299, GPU launch MSRP)
Qwen3 14B14.8B / 14.8B11.5 GB18.2 GBGeForce RTX 5060 Ti 16GB ($429, GPU launch MSRP)
Gemma 3 27B27.4B / 27.4B19.2 GB31.6 GBGeForce RTX 3090 ($1,499, GPU launch MSRP)
Qwen3 32B32.8B / 32.8B22.5 GB37.3 GBGeForce RTX 3090 ($1,499, GPU launch MSRP)
Qwen3 30B-A3B (MoE)30.5B / 3.3B21.1 GB34.9 GBGeForce RTX 3090 ($1,499, GPU launch MSRP)
gpt-oss-20b (MoE)21B / 3.6B13.7 GB24.8 GBGeForce RTX 5060 Ti 16GB ($429, GPU launch MSRP)
Llama 3.3 70B70.6B / 70.6B46.8 GB78.7 GBGMKtec EVO-X2 (128GB / 1TB) ($3,499.99, system, listed price)
gpt-oss-120b (MoE)117B / 5.1B64.7 GB126.8 GBGMKtec EVO-X2 (128GB / 1TB) ($3,499.99, system, listed price)
Qwen3 235B-A22B (MoE)235B / 22B146.1 GB252.2 GBNo single device in our dataset
Llama 3.1 405B405.9B / 405.9B253.3 GB436.5 GBNo single device in our dataset
DeepSeek-R1 671B (MoE)671B / 37B412.6 GB715.4 GBNo single device in our dataset

Parameter counts: Hugging Face: deepseek-ai/DeepSeek-R1 model card; Google: Gemma 3 model card; Hugging Face: openai/gpt-oss-120b model card; Hugging Face: meta-llama/Llama-3.1-8B; Hugging Face: meta-llama/Llama-3.3-70B-Instruct; Hugging Face: meta-llama/Llama-3.1-405B; Hugging Face: Qwen3 model cards (e.g. Qwen/Qwen3-30B-A3B). Memory figures are our estimates (see methodology), not measurements.

What changes the number

  • Quantization: 8-bit roughly doubles 4-bit memory; FP16 roughly quadruples it. See quantization explained.
  • Context length: the KV cache grows linearly with context.
  • Runtime: different engines add different overhead.
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