Free LLM VRAM calculator
Can your GPU or Mac run that AI model locally?
Pick a model and your hardware. See if it fits, which quantization to download, and how fast it will run.
New to local AI? Let us pick a model for you
“From a global allocation perspective, actually, it's quite terrible to have everybody have a bunch of the world's limited supply of DRAM sitting in their own computer.”
- 69open models
- 51GPUs and Macs
- 3519checked pairs
Both numbers are on the spec sheet. Bandwidth sets the speed estimate.
More options
KV cache: set OLLAMA_KV_CACHE_TYPE in Ollama (needs flash attention) or the K/V cache option in LM Studio. Click a quantization below to see its numbers.
ollama run llama3.1:8bRun it in the cloud
Rent a cloud GPU when your card is too small
No GPU, or not enough VRAM? Rent one by the hour and run any model today. No upfront cost, stop any time.
What each memory size runs
The largest model we track that runs well at Q4_K_M or better, 8K context.
| Memory | Largest model | Example GPU |
|---|---|---|
| 8 GB | RTX 5060 | |
| 12 GB | RTX 3080 Ti | |
| 16 GB | RTX 5080 | |
| 24 GB | RTX 4090 | |
| 32 GB | RTX 5090 | |
| 48 GB | Rent: RTX A6000, L40S | |
| 80 GB | Rent: A100, H100 |
Popular GPU and model checks
The questions people ask most, answered at 8K context.
Find your GPU or your model
Every page lists what runs, at which quantization, and how fast.
NVIDIA 26
- RTX 4060 8 GB
- RTX 4060 Ti 8GB 8 GB
- RTX 5060 8 GB
- RTX 5060 Ti 8GB 8 GB
- RTX 3060 Ti 8 GB
- RTX 3070 8 GB
- RTX 3080 10GB 10 GB
- RTX 2080 Ti 11 GB
- RTX 3060 12GB 12 GB
- RTX 4070 12 GB
- RTX 4070 Super 12 GB
- RTX 4070 Ti 12 GB
- RTX 5070 12 GB
- RTX 3080 Ti 12 GB
- RTX 4060 Ti 16GB 16 GB
- RTX 5060 Ti 16GB 16 GB
- RTX 4070 Ti Super 16 GB
- RTX 4080 16 GB
- RTX 4080 Super 16 GB
- RTX 5070 Ti 16 GB
- RTX 5080 16 GB
- RTX 3090 24 GB
- RTX 4090 24 GB
- RTX 3090 Ti 24 GB
- RTX 5090 32 GB
- RTX PRO 6000 Blackwell 96 GB
AMD 9
Qwen 23
DeepSeek 8
Mistral 8
Gemma 9
gpt-oss 2
Granite 1
Kimi 1
MiniMax 1
Nemotron 1
How GPU Fit estimates memory and speed
Token generation is limited by memory size and memory bandwidth, so both can be estimated from the spec sheet.
- WeightsParameters × bits per weight of the quantization.
- KV cache2 × layers × KV heads × head size × context × 2 bytes, with sliding-window layers capped at their window.
- Speed60% of peak bandwidth ÷ bytes of active weights per token.
Ask from your AI agent
The same estimates over MCP: check_fit, models_for_gpu, gpus_for_model.
{
"mcpServers": {
"gpufit": { "type": "http", "url": "https://gpufit.dev/mcp" }
}
}Questions about running LLMs locally
Short answers. The calculator above does the exact numbers for your hardware.
How much VRAM do I need to run an LLM locally?
At the popular Q4_K_M quantization, plan on roughly 0.6 GB per billion parameters plus 1 to 2 GB for context and overhead: about 6 GB for an 8B model, 10 GB for 14B, 21 GB for 32B and 44 GB for 70B at 8K context. Longer context needs more.
Which quantization should I use?
Use the highest quality quantization that fits fully in GPU memory. Q4_K_M is the usual sweet spot; Q5_K_M, Q6_K and Q8_0 are better if you have room; Q3 and Q2 noticeably hurt quality.
Can a Mac run local LLMs?
Yes. Apple Silicon Macs share memory between CPU and GPU, and macOS lets the GPU use about two thirds to three quarters of it by default, so a 64 GB or 128 GB Mac can run models that would need several consumer GPUs.
How are tokens per second estimated?
Generating text is limited by memory bandwidth: each token reads all active weights once. We estimate speed as 60% of the GPU's peak bandwidth divided by the size of the active weights.
What if my GPU is too small?
Use a smaller model or a lower quantization, offload some layers to system RAM (slow), or rent a cloud GPU by the hour.