Gemma 4 12B VRAM requirements
Gemma 4 12B needs about 8.57 GB of VRAM at Q4_K_M with 8K context, so it fits a 12 GB card such as the RTX 3060 12GB or the RTX 4070 12GB. Gemma 4 12B has 12.0B parameters. With the same 8K context and one request it needs 13.4 GB at FP8 and 25.7 GB at FP16/BF16. The published weights take 22.3 GB (BF16). The smallest setup here that holds it at Q4_K_M with an 8K context is the RTX 3060 12GB; on one 24 GB RTX 3090 / 4090 it runs with its full 256K-token context.
8.57 GB at Q4_K_M, 8K context, one request
- FP8
- 13.4 GB
- FP16 / BF16
- 25.7 GB
- Published weights
- 22.3 GB
- Smallest setup, Q4_K_M
- RTX 3060 12GB
Worked example: Gemma 4 12B with 32K tokens
Inputs: Gemma 4 12B · Q4_K_M weights · 32,768 tokens of context · one request · FP16 KV cache
- Weights (12.0B at Q4_K_M)
- 6.74 GB
- KV cache (16 KB per token)
- 992 MB
- Buffers and runtime (0.5 GB + 10%)
- 1.27 GB
- Total
- 8.98 GB
The smallest setup here that holds it is the RTX 3060 12GB, with about 3.02 GB to spare. Change the inputs in the calculator
Can I run Gemma 4 12B on…
- RTX 4090: Yes, up to Q8_0
- RTX 3090: Yes, up to Q8_0
- RTX 3060 12GB: Yes, up to Q5_K_M
- RTX 4060 Ti 16GB: Yes, up to Q8_0
- RTX 5060 Ti 16GB: Yes, up to Q8_0
- RTX 4070 12GB: Yes, up to Q5_K_M
- RTX 5080 16GB: Yes, up to Q8_0
- RTX 4080 Super 16GB: Yes, up to Q8_0
- RX 7900 XTX: Yes, up to Q8_0
What makes Gemma 4 12B's memory use different
Its 40 sliding-window layers keep only the last 1,024 tokens (llama.cpp gives them 1,536 cells: the window plus a 512-token batch, rounded up to 256): at its 256K limit they hold 480 MB of cache instead of the 80.0 GB they would need with full attention.
Per token of context it adds 16 KB of FP16 cache; Granite 4.2 8B (8.8B), the nearest-sized model here with plain full attention, adds 160 KB, so Gemma 4 12B needs 10% as much.
How much VRAM does Gemma 4 12B need?
Gemma 4 12B needs 8.57 GB at Q4_K_M, 14.2 GB at Q8_0 and 25.7 GB at FP16 with 8,192 tokens of context and one request. Each total below is the weights plus the FP16 KV cache and the runtime overhead (0.5 GB plus 10%), and each row opens the calculator with that setting. What the GGUF names mean.
| Precision | Weights | Total | Smallest setup |
|---|---|---|---|
| As published (BF16) | 22.3 GB | 25.7 GB | RTX 5090 (32 GB) |
| FP16 / BF16 | 22.3 GB | 25.7 GB | RTX 5090 (32 GB) |
| FP8 / INT8 | 11.1 GB | 13.4 GB | RTX 4060 Ti 16GB |
| INT4 (AWQ / GPTQ) | 5.92 GB | 7.66 GB | RTX 4060 8GB |
| GGUF Q8_0 | 11.8 GB | 14.2 GB | RTX 4060 Ti 16GB |
| GGUF Q6_K | 9.13 GB | 11.2 GB | RTX 3060 12GB |
| GGUF Q5_K_M | 7.89 GB | 9.84 GB | RTX 3060 12GB |
| GGUF Q4_K_M | 6.74 GB | 8.57 GB | RTX 3060 12GB |
| GGUF IQ4_XS | 6.06 GB | 7.82 GB | RTX 4060 8GB |
| GGUF Q3_K_M | 5.44 GB | 7.14 GB | RTX 4060 8GB |
| GGUF IQ3_XXS | 4.59 GB | 6.21 GB | RTX 4060 8GB |
| GGUF Q2_K | 4.66 GB | 6.28 GB | RTX 4060 8GB |
Fine-tuning Gemma 4 12B? Gemma 4 12B VRAM for LoRA, QLoRA and full training.
Gemma 4 12B GGUF files on Hugging Face
The 8 GGUF files llama.cpp picks for Gemma 4 12B with -hf <repo>:<QUANT>, with the bytes the Hugging Face file list reported on 2026-09-29. Each total is that file plus the FP16 KV cache and 0.5 GB + 10%, one request. "vs estimate" compares the file with the bits-per-weight size the table above uses.
| Quant | File | Size | vs estimate | 8K | 32K | 128K |
|---|---|---|---|---|---|---|
| Q2_K | bartowski/ | 4.73 GB5,077,875,168 bytes | +1% | 6.36 GB | 6.77 GB | 8.42 GB |
| Q3_K_M | unsloth/ | 5.30 GB5,693,872,960 bytes | −3% | 6.99 GB | 7.40 GB | 9.05 GB |
| IQ4_XS | unsloth/ | 5.94 GB6,375,734,080 bytes | −2% | 7.68 GB | 8.10 GB | 9.75 GB |
| Q4_K_M | unsloth/ | 6.63 GB7,121,861,440 bytes | −2% | 8.45 GB | 8.86 GB | 10.5 GB |
| Q5_K_M | unsloth/ | 7.84 GB8,413,576,000 bytes | −1% | 9.77 GB | 10.2 GB | 11.8 GB |
| Q6_K | unsloth/ | 9.11 GB9,786,022,720 bytes | ±0% | 11.2 GB | 11.6 GB | 13.2 GB |
| Q8_0 | ggml-org/ | 11.8 GB12,669,646,976 bytes | ±0% | 14.1 GB | 14.5 GB | 16.2 GB |
| BF16 | ggml-org/ | 22.2 GB23,832,066,176 bytes | ±0% | 25.6 GB | 26.0 GB | 27.6 GB |
GB here is GiB (1024³ bytes), as everywhere on this site; Hugging Face shows the Q4_K_M file as 7.1 GB, in 10⁹ bytes.
Gemma 4 12B Heretic (decensored) variants
Heretic removes refusals from a model automatically: it ablates the "refusal direction" in the weights and tunes the ablation to keep the output close to the original. igorls/
It is the same model with edited weights, not a new architecture: its safetensors take 23,919,548,424 bytes against 23,919,549,408 for google/
| Quant | File | Size | 8K | 32K | 128K |
|---|---|---|---|---|---|
| Q4_K_M | igorls/ | 6.87 GB7,381,381,760 bytes | 8.72 GB | 9.13 GB | 10.8 GB |
| Q8_0 | igorls/ | 11.8 GB12,669,645,440 bytes | 14.1 GB | 14.5 GB | 16.2 GB |
| IQ3_XS | culturerevolt/ | 4.91 GB5,272,393,056 bytes | 6.55 GB | 6.97 GB | 8.62 GB |
| IQ4_XS | culturerevolt/ | 6.18 GB6,635,255,136 bytes | 7.95 GB | 8.36 GB | 10.0 GB |
| Q4_K_M | culturerevolt/ | 6.87 GB7,381,382,496 bytes | 8.72 GB | 9.13 GB | 10.8 GB |
| Q5_K_M | culturerevolt/ | 7.96 GB8,547,267,936 bytes | 9.91 GB | 10.3 GB | 12.0 GB |
| Q6_K | culturerevolt/ | 9.11 GB9,786,021,216 bytes | 11.2 GB | 11.6 GB | 13.2 GB |
| Q8_0 | culturerevolt/ | 11.8 GB12,669,645,440 bytes | 14.1 GB | 14.5 GB | 16.2 GB |
| UD-Q4_K_XL (QAT) | SC117/ | 6.26 GB6,716,355,776 bytes | 8.03 GB | 8.45 GB | 10.1 GB |
The Heretic Q4_K_M files are 259,520,320 bytes (0.24 GB) larger than the unsloth Q4_K_M above; the Q8_0 files are within 2 KB of ggml-org's. For images, both culturerevolt and SC117 ship the 175,115,840-byte (0.16 GB) vision projector (mmproj) as a separate file, which adds that much to the totals. File sizes from the Hugging Face file lists, read on ; totals as in the table above, one request, FP16 KV cache.
Which Gemma 4 12B GGUF fits a 16, 24, 32, 48 or 80 GB GPU or a Mac
From the file sizes above: the largest file that fits each machine with an 8K context and 0.5 GB left free, the longest context it then has room for, and the longest context for Q4_K_M (6.63 GB). One request, FP16 KV cache, -np 1. The Q4_K_M file is 109 MB under its bits-per-weight estimate; the estimate tables and the llama-server command on this page count the estimate, so they show less context.
| Hardware | Largest GGUF, 8K | Its longest context | Q4_K_M, longest context |
|---|---|---|---|
| RTX 5060 Ti 16GB | Q8_0, 11.8 GB | 87K | 256K (full) |
| RTX 4090 (24 GB) | Q8_0, 11.8 GB | 256K (full) | 256K (full) |
| RTX 5090 (32 GB) | BF16, 22.2 GB | 256K (full) | 256K (full) |
| L40S (48 GB) | BF16, 22.2 GB | 256K (full) | 256K (full) |
| H100 SXM (80 GB) | BF16, 22.2 GB | 256K (full) | 256K (full) |
| M4 Pro Mac (64 GB, 48 GB usable) | BF16, 22.2 GB | 256K (full) | 256K (full) |
| M4 Max Mac (128 GB, 96 GB usable) | BF16, 22.2 GB | 256K (full) | 256K (full) |
Run Gemma 4 12B with llama.cpp or Ollama
llama-server -hf unsloth/gemma-4-12b-it-GGUF:Q4_K_M -c 262144 -np 1 gemma-4-12b-it-Q4_K_M.gguf, 7.1 GB, from unsloth/
ollama run gemma4:12b
Ollama library tag gemma4:12b; its quant is Ollama's choice. Same context: /set parameter num_ctx 262144.
Gemma 4 12B at 8K, 32K, 128K and 256K (full) tokens of context
8 of its 48 layers use full attention and 40 keep a sliding window of 1,024 tokens. Each extra token of context adds 16 KB of FP16 cache per request once the sliding windows are full. The last column is the smallest setup here, one card or a group, that holds it at Q4_K_M. How the KV cache works.
| Context | KV cache, FP16 | Total at Q4_K_M | Total at Q8_0 | Smallest setup, Q4_K_M |
|---|---|---|---|---|
| 8K tokens | 608 MB | 8.57 GB | 14.2 GB | RTX 3060 12GB |
| 32K tokens | 992 MB | 8.98 GB | 14.6 GB | RTX 3060 12GB |
| 128K tokens | 2.47 GB | 10.6 GB | 16.2 GB | RTX 3060 12GB |
| 256K tokens | 4.47 GB | 12.8 GB | 18.4 GB | RTX 4060 Ti 16GB |
How fast Gemma 4 12B writes
Tokens per second for one request with 8,192 tokens of context, estimated from memory bandwidth. A dash means it does not fit on one card. Try other settings in the speed calculator.
| Hardware | Bandwidth | Q4_K_M | FP8 |
|---|---|---|---|
| RTX 3060 12GB | 360 GB/s | 24–34 | — |
| RTX 4090 | 1,008 GB/s | 64–92 | 41–58 |
| RTX 5090 | 1,792 GB/s | 105–157 | 70–101 |
| M4 Max Mac (128 GB) | 546 GB/s | 36–51 | 23–32 |
| M3 Ultra Mac Studio (512 GB) | 819 GB/s | 53–75 | 34–48 |
| H100 SXM | 3,350 GB/s | 173–275 | 120–181 |
| H200 | 4,800 GB/s | 223–372 | 159–250 |
Longest context on one GPU
How many tokens of context Gemma 4 12B fits on a single card with one request, an FP16 KV cache and 0.5 GB left free. "Full" means the model's whole context window fits.
| GPU | Memory | Q4_K_M | Q8_0 | FP8 |
|---|---|---|---|---|
| RTX 3060 | 12 GB | 178K | No | No |
| RTX 4060 Ti 16GB | 16 GB | 256K (full) | 85K | 129K |
| RTX 3090 / 4090 | 24 GB | 256K (full) | 256K (full) | 256K (full) |
| RTX 5090 | 32 GB | 256K (full) | 256K (full) | 256K (full) |
| A100 40GB | 40 GB | 256K (full) | 256K (full) | 256K (full) |
| Mac, 64 GB unified memory | 48 GB | 256K (full) | 256K (full) | 256K (full) |
| L40S / RTX 6000 Ada | 48 GB | 256K (full) | 256K (full) | 256K (full) |
| A100 / H100 80GB | 80 GB | 256K (full) | 256K (full) | 256K (full) |
| Mac, 128 GB unified memory | 96 GB | 256K (full) | 256K (full) | 256K (full) |
| H200 | 141 GB | 256K (full) | 256K (full) | 256K (full) |
| B200 | 180 GB | 256K (full) | 256K (full) | 256K (full) |
Model details
- Parameters
- 12.0B (11,959,730,224)
- Layers
- 8 of its 48 layers use full attention and 40 keep a sliding window of 1,024 tokens
- Attention cache
- 1 KV heads × 512 (values come from the key projection but are cached separately)
- Sliding-window layers
- 8 KV heads × 256
- Context length
- 262,144 tokens
- Published weights
- 22.3 GB (BF16)
- On Hugging Face
- google/
gemma-4-12B-it
Why this estimate looks this way
At Q4_K_M and an 8K-token context, Gemma 4 12B uses 6.74 GB for weights, 608 MB for its FP16 KV cache and 1.23 GB for estimated runtime overhead, totaling 8.57 GB. The overhead is a 0.5 GB base plus 10% of weights and cache.
Its attention layout matters for long context: 8 of its 48 layers use full attention and 40 keep a sliding window of 1,024 tokens. The FP16 cache grows by about 16 KB per additional token per request once the sliding windows are full.
The architecture and published checkpoint size come from the model's config.json and weight files. These are estimates rather than measured peak memory; inference engines can reserve extra buffers or preallocate the full configured cache.
Gemma 4 12B next to similar-sized models
The three models here closest to it in parameter count, at Q4_K_M with 8,192 tokens of context.
| Model | Parameters | Total | KV per token | Smallest setup |
|---|---|---|---|---|
| Gemma 4 12B | 12.0B | 8.57 GB | 16 KB | RTX 3060 12GB |
| ZDTaichu 5.0 9B | 9.8B | 6.85 GB | 32 KB | RTX 4060 8GB |
| Ornith 1.5 9B | 9.7B | 6.76 GB | 32 KB | RTX 4060 8GB |
| Qwen3.5 9B | 9.7B | 6.76 GB | 32 KB | RTX 4060 8GB |
Gemma 4 12B VRAM questions
How much VRAM do I need to run Gemma 4 12B locally?
About 8.57 GB at Q4_K_M with an 8K context and one request, by the bits-per-weight estimate, and 25.7 GB at BF16. The Q4_K_M GGUF gemma-4-12b-it-Q4_K_M.gguf in unsloth/
Can I run Gemma 4 12B on a 24 GB GPU?
Yes. On the RTX 4090 (24 GB), the largest listed GGUF that fits with an 8K context and 0.5 GB free is Q8_0 (11.8 GB), with its full 256K-token context.
Which quantization of Gemma 4 12B fits in 16 GB of VRAM?
On the RTX 5060 Ti 16GB, the largest listed GGUF that fits with an 8K context and 0.5 GB free is Q8_0 (11.8 GB), with up to 87K tokens of context. Q4_K_M (6.63 GB) runs with its full 256K-token context.
Can I run Gemma 4 12B on a Mac?
On the M4 Pro Mac (64 GB, 48 GB usable), the largest listed GGUF that fits with an 8K context and 0.5 GB free is BF16 (22.2 GB), with its full 256K-token context. On the M4 Max Mac (128 GB, 96 GB usable), the largest listed GGUF that fits with an 8K context and 0.5 GB free is BF16 (22.2 GB), with its full 256K-token context. By default macOS lets the GPU use about 75% of unified memory.
How much more VRAM does Gemma 4 12B need for 32K or 128K tokens of context?
Its FP16 KV cache is 608 MB at 8K, 992 MB at 32K, 2.47 GB at 128K for one request, so 128K adds 1.88 GB over 8K, plus 10% overhead. A q8_0 cache
Why does Gemma 4 12B use more VRAM than its GGUF file size?
The file holds only the weights. At Q4_K_M with an 8K context: 6.63 GB of weights (the file's 7,121,861,440 bytes) + 608 MB of FP16 KV cache + 1.22 GB of compute buffers and runtime (0.5 GB + 10%) = 8.45 GB.
Badge for your model card
Paste it into a Hugging Face or GitHub README; it shows the Q4_K_M total above and links to this page. Q8_0 and FP16 badges.
Numbers read from the model files on Hugging Face on . Compare it with other models in the reproducible model and GPU report.