aiAI Calculator Pro

GPU VRAM Calculator for LLMs

Estimate the VRAM needed to run a model locally.

Results update automatically as you type.

Result
~168 GB VRAM
≈ 3 x 80 GB GPU(s) to serve
Parameters
70 B
Precision
fp16
Weights + overhead
168 GB
GPUs needed
3

Estimate how much GPU memory a model needs based on its parameter count and precision, and how many GPUs it takes to serve — essential before running models locally.

How this is calculated

This calculator uses the infrastructure formulas described in our methodology. All figures are estimates for planning; verify current pricing with each provider before relying on them.

Worked example (defaults)

With the default inputs above, here is the result:

Result
~168 GB VRAM
≈ 3 x 80 GB GPU(s) to serve
Parameters
70 B
Precision
fp16
Weights + overhead
168 GB
GPUs needed
3

Frequently asked questions

How much VRAM does a 70B model need?+

About 168 GB at float16 (2 bytes/param + overhead), so 2–3 high-end 80 GB GPUs. int4 quantization drops it to ~42 GB.

What's the overhead for?+

KV cache, activations and framework overhead on top of the raw weights, roughly 15–30%.

Related calculators