Granite 4.2 30B VRAM requirements
Granite 4.2 30B has 29.3B parameters. With an 8K-token context and one request it needs about 20.8 GB of GPU memory at Q4_K_M, 32.7 GB at FP8 and 62.7 GB at FP16/BF16. The published weights take 54.5 GB (BF16). The smallest setup here that holds it at Q4_K_M with an 8K context is the RTX 3090 (24 GB), which runs it with up to 17K tokens of context.
20.8 GB at Q4_K_M, 8K context, one request
- FP8
- 32.7 GB
- FP16 / BF16
- 62.7 GB
- Published weights
- 54.5 GB
- Smallest setup, Q4_K_M
- RTX 3090 (24 GB)
Worked example: Granite 4.2 30B with 32K tokens
Inputs: Granite 4.2 30B · Q4_K_M weights · 32,768 tokens of context · one request · FP16 KV cache
- Weights (29.3B at Q4_K_M)
- 16.5 GB
- KV cache (256 KB per token)
- 8.00 GB
- Buffers and runtime (0.5 GB + 10%)
- 2.95 GB
- Total
- 27.4 GB
The smallest setup here that holds it is the RTX 5090 (32 GB), with about 4.55 GB to spare. Change the inputs in the calculator
How much VRAM does Granite 4.2 30B need?
Granite 4.2 30B needs 20.8 GB at Q4_K_M, 34.6 GB at Q8_0 and 62.7 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) | 54.5 GB | 62.7 GB | 2× RTX 5090 (64 GB) |
| FP16 / BF16 | 54.5 GB | 62.7 GB | 2× RTX 5090 (64 GB) |
| FP8 / INT8 | 27.3 GB | 32.7 GB | M4 Pro Mac (64 GB, 48 GB usable) |
| INT4 (AWQ / GPTQ) | 14.5 GB | 18.6 GB | RTX 3090 (24 GB) |
| GGUF Q8_0 | 29.0 GB | 34.6 GB | M4 Pro Mac (64 GB, 48 GB usable) |
| GGUF Q6_K | 22.4 GB | 27.3 GB | RTX 5090 (32 GB) |
| GGUF Q5_K_M | 19.3 GB | 24.0 GB | RTX 3090 (24 GB) |
| GGUF Q4_K_M | 16.5 GB | 20.8 GB | RTX 3090 (24 GB) |
| GGUF IQ4_XS | 14.8 GB | 19.0 GB | RTX 3090 (24 GB) |
| GGUF Q3_K_M | 13.3 GB | 17.4 GB | RTX 3090 (24 GB) |
| GGUF IQ3_XXS | 11.2 GB | 15.1 GB | RTX 4060 Ti 16GB |
| GGUF Q2_K | 11.4 GB | 15.3 GB | RTX 4060 Ti 16GB |
Fine-tuning Granite 4.2 30B? Granite 4.2 30B VRAM for LoRA, QLoRA and full training.
Granite 4.2 30B GGUF files on Hugging Face
The 8 GGUF files llama.cpp picks for Granite 4.2 30B 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/ | 10.4 GB11,122,897,952 bytes | −9% | 14.1 GB | 20.7 GB | 47.1 GB |
| Q3_K_M | bartowski/ | 13.4 GB14,358,606,880 bytes | ±0% | 17.4 GB | 24.0 GB | 50.4 GB |
| IQ4_XS | bartowski/ | 14.8 GB15,910,302,752 bytes | ±0% | 19.0 GB | 25.6 GB | 52.0 GB |
| Q4_K_M | bartowski/ | 16.8 GB18,027,639,840 bytes | +2% | 21.2 GB | 27.8 GB | 54.2 GB |
| Q5_K_M | bartowski/ | 19.6 GB21,025,518,624 bytes | +1% | 24.2 GB | 30.8 GB | 57.2 GB |
| Q6_K | bartowski/ | 22.8 GB24,508,953,632 bytes | +2% | 27.8 GB | 34.4 GB | 60.8 GB |
| Q8_0 | bartowski/ | 29.0 GB31,111,705,632 bytes | ±0% | 34.6 GB | 41.2 GB | 67.6 GB |
| BF16 | bartowski/ | 54.5 GB58,558,182,304 bytes | ±0% | 62.7 GB | 69.3 GB | 95.7 GB |
GB here is GiB (1024³ bytes), as everywhere on this site; Hugging Face shows the Q4_K_M file as 18.0 GB, in 10⁹ bytes.
Which Granite 4.2 30B 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 (16.8 GB). One request, FP16 KV cache.
| Hardware | Largest GGUF, 8K | Its longest context | Q4_K_M, longest context |
|---|---|---|---|
| RTX 5060 Ti 16GB | Q2_K, 10.4 GB | 12K | No |
| RTX 4090 (24 GB) | Q4_K_M, 16.8 GB | 16K | 16K |
| RTX 5090 (32 GB) | Q6_K, 22.8 GB | 21K | 45K |
| L40S (48 GB) | Q8_0, 29.0 GB | 54K | 103K |
| H100 SXM (80 GB) | BF16, 54.5 GB | 68K | 128K (full) |
| M4 Pro Mac (64 GB, 48 GB usable) | Q8_0, 29.0 GB | 54K | 103K |
| M4 Max Mac (128 GB, 96 GB usable) | BF16, 54.5 GB | 127K | 128K (full) |
Run Granite 4.2 30B with llama.cpp or Ollama
llama-server -hf bartowski/granite-4.2-30b-GGUF:Q4_K_M -c 16384 granite-4.2-30b-Q4_K_M.gguf, 18.0 GB, from bartowski/
ollama run granite4.2:30b
Ollama library tag granite4.2:30b; its quant is Ollama's choice. Same context: /set parameter num_ctx 16384.
Granite 4.2 30B at 8K, 32K and 128K (full) tokens of context
All 64 layers use full attention. Each extra token of context adds 256 KB of FP16 cache per request. 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 | 2.00 GB | 20.8 GB | 34.6 GB | RTX 3090 (24 GB) |
| 32K tokens | 8.00 GB | 27.4 GB | 41.2 GB | RTX 5090 (32 GB) |
| 128K tokens | 32.0 GB | 53.8 GB | 67.6 GB | 2× RTX 5090 (64 GB) |
How fast Granite 4.2 30B 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 | — | — |
| RTX 4090 | 1,008 GB/s | 27–37 | — |
| RTX 5090 | 1,792 GB/s | 46–65 | — |
| M4 Max Mac (128 GB) | 546 GB/s | 15–20 | 9.4–13 |
| M3 Ultra Mac Studio (512 GB) | 819 GB/s | 22–30 | 14–19 |
| H100 SXM | 3,350 GB/s | 81–119 | 54–77 |
| H200 | 4,800 GB/s | 111–166 | 75–108 |
Longest context on one GPU
How many tokens of context Granite 4.2 30B 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 | No | No | No |
| RTX 4060 Ti 16GB | 16 GB | No | No | No |
| RTX 3090 / 4090 | 24 GB | 17K | No | No |
| RTX 5090 | 32 GB | 46K | No | 3K |
| A100 40GB | 40 GB | 75K | 25K | 32K |
| Mac, 64 GB unified memory | 48 GB | 104K | 54K | 61K |
| L40S / RTX 6000 Ada | 48 GB | 104K | 54K | 61K |
| A100 / H100 80GB | 80 GB | 128K (full) | 128K (full) | 128K (full) |
| Mac, 128 GB unified memory | 96 GB | 128K (full) | 128K (full) | 128K (full) |
| H200 | 141 GB | 128K (full) | 128K (full) | 128K (full) |
| B200 | 180 GB | 128K (full) | 128K (full) | 128K (full) |
Model details
- Parameters
- 29.3B (29,276,770,304)
- Layers
- All 64 layers use full attention
- Attention cache
- 8 KV heads × 128
- Context length
- 131,072 tokens
- Published weights
- 54.5 GB (BF16)
- On Hugging Face
- ibm-granite/
granite-4.2-30b
Why this estimate looks this way
At Q4_K_M and an 8K-token context, Granite 4.2 30B uses 16.5 GB for weights, 2.00 GB for its FP16 KV cache and 2.35 GB for estimated runtime overhead, totaling 20.8 GB. The overhead is a 0.5 GB base plus 10% of weights and cache.
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.
Granite 4.2 30B 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 |
|---|---|---|---|---|
| Granite 4.2 30B | 29.3B | 20.8 GB | 256 KB | RTX 3090 (24 GB) |
| Muse Glimmer 30B | 29.8B | 19.2 GB | 13 KB | RTX 3090 (24 GB) |
| Qwen3-Coder 30B-A3B | 30.5B, 3.3B active | 20.2 GB | 96 KB | RTX 3090 (24 GB) |
| Qwen3 30B-A3B | 30.5B, 3.3B active | 20.2 GB | 96 KB | RTX 3090 (24 GB) |
Granite 4.2 30B VRAM questions
How much VRAM do I need to run Granite 4.2 30B locally?
About 20.8 GB at Q4_K_M with an 8K context and one request, by the bits-per-weight estimate, and 62.7 GB at BF16. The Q4_K_M GGUF granite-4.2-30b-Q4_K_M.gguf in bartowski/
Can I run Granite 4.2 30B 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 Q4_K_M (16.8 GB), with up to 16K tokens of context.
Which quantization of Granite 4.2 30B 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 Q2_K (10.4 GB), with up to 12K tokens of context.
Can I run Granite 4.2 30B 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 Q8_0 (29.0 GB), with up to 54K tokens of context. Q4_K_M (16.8 GB) runs with up to 103K tokens of 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 (54.5 GB), with up to 127K tokens of context. Q4_K_M (16.8 GB) runs with its full 128K-token context. By default macOS lets the GPU use about 75% of unified memory.
How much more VRAM does Granite 4.2 30B need for 32K or 128K tokens of context?
Its FP16 KV cache is 2.00 GB at 8K, 8.00 GB at 32K, 32.0 GB at 128K for one request, so 128K adds 30.0 GB over 8K, plus 10% overhead. A q8_0 cache
Why does Granite 4.2 30B use more VRAM than its GGUF file size?
The file holds only the weights. At Q4_K_M with an 8K context: 16.8 GB of weights (the file's 18,027,639,840 bytes) + 2.00 GB of FP16 KV cache + 2.38 GB of compute buffers and runtime (0.5 GB + 10%) = 21.2 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.