How much VRAM to run Llama 3.1 8B?

About 8 GB atQ4_K_M with an 8K context — fits a RTX 3060 12GB. Full breakdown below, or check your exact hardware.

Llama 3.1 8B VRAM by quantisation

QuantisationWeightsTotal (8K ctx)Fits on
Q4_K_M4.9 GB7.6 GBRTX 3060 12GB, RTX 5060 Ti 16GB
Q5_K_M5.7 GB8.5 GBRTX 3060 12GB, RTX 5060 Ti 16GB
Q6_K6.6 GB9.4 GBRTX 3060 12GB, RTX 5060 Ti 16GB
Q8_08.6 GB11.6 GBRTX 3060 12GB, RTX 5060 Ti 16GB
FP16 / BF1616.1 GB19.8 GBRX 7900 XTX, RTX 4090

Check your hardware

About Llama 3.1 8B

Llama 3.1 8B is Meta's 8.03B-parameter model released in July 2024, with a 128K-token context window. It uses a classic dense-attention design whose KV cache grows linearly with context: its KV cache is about 1.1 GB at an 8K context, 17.2 GB at 128K, and 17.2 GB at the full 128K window (FP16 cache).

For most people Q4_K_M is the sweet spot — the most popular quality/size trade-off — while Q8 is near-lossless if you have the memory. Totals above include the KV cache and a realistic framework overhead, so they are what you should expect to see in practice rather than just the download size. Weight sizes are calibrated against real GGUF files — see themethodology.

Frequently asked questions

How much VRAM does Llama 3.1 8B need?

At Q4_K_M with an 8K context, Llama 3.1 8B needs about 8 GB (weights 5 GB + KV cache + overhead). The smallest common hardware that fits is a RTX 3060 12GB.

Can an RTX 4090 (24GB) run Llama 3.1 8B?

Yes. An RTX 4090's 24 GB runs Llama 3.1 8B at FP16 / BF16 (about 20 GB at 8K context) — at full FP16 precision.

Can a Mac run Llama 3.1 8B?

Yes — Apple Silicon with 16 GB of unified memory or more (macOS lets the GPU use ~75% of it, ~12 GB) runs Llama 3.1 8B at Q4_K_M.

Related

VRAM calculator for any model ·Token counter

Last updated 2026-08-03. Architecture figures from the model's published config.json; see themethodology.