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How much VRAM does Gemma 3 27B need?

Gemma 3 · 27B params · updated 2026-08-25

Headline answer

At bf16, reference 8K context, batch size 1: 58.7GB of VRAM. The smallest fitting configuration is 1× H100 PCIe 80GB.

VRAM by quantization

DtypeVRAMFits on
bf16 58.7GB 1× H100 PCIe 80GB
fp8 32.3GB 1× L40 48GB
awq 23.0GB 1× RTX 5000 Ada 32GB
nvfp4 24.0GB 1× RTX 5000 Ada 32GB

Context length sensitivity

Same model, same bf16 dtype, batch size 1 — VRAM at longer context windows.

ContextVRAM (bf16)
8K58.7GB
32K60.8GB
128K68.8GB

Model facts

Parameters 27B
Architecture dense
Max context 131,072

About Gemma 3 27B

Running a Gemma 3 27B in bf16 at a reference 8K context and batch size 1 takes 58.7GB of VRAM — a number our calculator derives from the model's published architecture (layer count, hidden size, attention heads), not a rough rule of thumb. Gemma 3 27B is a Gemma 3 model with 27B parameters, and at this batch size that VRAM figure is dominated by the weights themselves, with KV cache and framework overhead adding a smaller but still meaningful slice on top. Which GPU you actually need depends heavily on quantization: bf16 is the reference precision with no quality loss, but fp8 roughly halves the weight footprint, AWQ (weight-only int4) goes further still, and — on Blackwell hardware — NVFP4 offers a similar 4-bit footprint with hardware-native throughput. At bf16, the smallest configuration that fits this model is 1× H100 PCIe 80GB; the dtype table above shows exactly how that changes as you quantize down, including whether a smaller or cheaper GPU becomes viable. Context length is the other lever: KV cache grows roughly linearly with how many tokens you keep resident, so a deployment serving long documents or long conversations needs meaningfully more headroom than this 8K reference number suggests — see the context-sensitivity table for how VRAM scales at 32K and 128K where this model's native context allows it. If you're sizing a real deployment rather than just checking whether a model fits, feed these same architecture numbers into the full calculator to model your actual concurrency and serving framework.

Frequently asked questions

How much VRAM does Gemma 3 27B need?

At bf16, reference 8K context and batch size 1, Gemma 3 27B needs 58.7GB of VRAM. The smallest fitting configuration we find is 1× H100 PCIe 80GB.

How many parameters does Gemma 3 27B have?

Gemma 3 27B has 27B parameters (dense — every parameter is active on every token).

Does quantization reduce Gemma 3 27B's VRAM requirement?

Yes — switching from bf16 to fp8 brings the total down to 32.3GB, and weight-only int4 formats (AWQ, NVFP4) go further still. See the per-dtype table above for exact numbers.

Where do these VRAM numbers come from?

They're computed by the same calculator engine behind our interactive GPU calculator, from the model's published architecture (layers, hidden size, attention heads, KV cache config) — not a generic per-parameter estimate.

Methodology: VRAM figures are computed by the same calculator engine behind our interactive GPU calculator, from Gemma 3 27B's published architecture (layer count, hidden size, attention heads, KV cache configuration) — not a generic per-parameter estimate. Reference scenario: batch size 1, vLLM framework, fp16 KV cache. Page last updated 2026-08-25. These are engineering estimates, not a guarantee — always validate against your actual serving framework and workload before committing to hardware.

Size a full deployment — concurrency, framework, quantization — in the calculator →