gemma-2-27b-it
google/gemma-2-27b-itgemma-2-27b-it at Q4_K_M is exactly 16,645,381,632 bytes (15.50 GiB / 16.65 GB) — an effective 4.891 bits per weight, not the nominal 4. Its KV cache at 32K is 6.56 GiB, not the 11.50 GiB a flat formula predicts.
Shipped quantizations
| Quant | Size● | Exact bytes● | Effective bpw● | Tensors● | Publisher |
|---|---|---|---|---|---|
| IQ1_S | 5.71 GiB | 6,132,432,896 | 1.802 | — | legraphista |
| IQ1_M | 6.23 GiB | 6,692,470,784 | 1.966 | — | legraphista |
| IQ2_XXS | 7.10 GiB | 7,625,867,264 | 2.241 | — | legraphista |
| IQ2_XS | 7.82 GiB | 8,399,716,352 | 2.468 | — | legraphista |
| IQ2_XS | 7.82 GiB | 8,399,716,832 | 2.468 | — | bartowski |
| IQ2_S | 8.06 GiB | 8,652,161,024 | 2.542 | — | legraphista |
| IQ2_S | 8.06 GiB | 8,652,161,504 | 2.542 | — | bartowski |
| IQ2_M | 8.75 GiB | 9,398,877,696 | 2.762 | — | bartowski |
| IQ2_M | 8.75 GiB | 9,398,878,208 | 2.762 | — | legraphista |
| Q2_K_S | 9.06 GiB | 9,722,765,312 | 2.857 | — | legraphista |
| Q2_K | 9.73 GiB | 10,449,575,424 | 3.070 | — | bartowski |
| Q2_K | 9.73 GiB | 10,449,575,936 | 3.070 | — | legraphista |
| Q2_K_L | 10.00 GiB | 10,735,271,424 | 3.154 | — | bartowski |
| IQ3_XXS | 10.01 GiB | 10,750,754,304 | 3.159 | — | bartowski |
| IQ3_XXS | 10.01 GiB | 10,750,754,816 | 3.159 | — | legraphista |
| IQ3_XS | 10.76 GiB | 11,550,629,376 | 3.394 | — | bartowski |
| IQ3_XS | 10.76 GiB | 11,550,629,888 | 3.394 | — | legraphista |
| Q3_K_S | 11.33 GiB | 12,169,059,840 | 3.576 | — | bartowski |
| Q3_K_S | 11.33 GiB | 12,169,060,352 | 3.576 | — | legraphista |
| IQ3_S | 11.33 GiB | 12,169,060,352 | 3.576 | — | legraphista |
| IQ3_M | 11.60 GiB | 12,454,829,568 | 3.659 | — | bartowski |
| IQ3_M | 11.60 GiB | 12,454,830,080 | 3.659 | — | legraphista |
| IQ3_M | 11.60 GiB | 12,454,830,560 | 3.659 | — | lmstudio-community |
| Q3_K_M | 12.50 GiB | 13,424,647,680 | 3.945 | — | bartowski |
| Q3_K | 12.50 GiB | 13,424,648,192 | 3.945 | — | legraphista |
| Q3_K_L | 13.52 GiB | 14,519,361,024 | 4.266 | — | bartowski |
| Q3_K_L | 13.52 GiB | 14,519,361,536 | 4.266 | — | legraphista |
| Q3_K_L | 13.52 GiB | 14,519,362,016 | 4.266 | — | lmstudio-community |
| IQ4_XS | 13.80 GiB | 14,814,420,480 | 4.353 | — | bartowski |
| IQ4_XS | 13.80 GiB | 14,814,420,992 | 4.353 | — | legraphista |
| IQ4_XS | 13.80 GiB | 14,814,421,472 | 4.353 | — | lmstudio-community |
| IQ4_NL | 14.56 GiB | 15,628,378,112 | 4.592 | — | legraphista |
| Q4_K_S | 14.66 GiB | 15,739,264,512 | 4.625 | — | bartowski |
| Q4_K_S | 14.66 GiB | 15,739,265,024 | 4.625 | — | legraphista |
| Q4_K_M | 15.50 GiB | 16,645,381,632 | 4.891 | — | bartowski |
| Q4_K | 15.50 GiB | 16,645,382,144 | 4.891 | — | legraphista |
| Q4_K_M | 15.50 GiB | 16,645,382,624 | 4.891 | — | lmstudio-community |
| Q4_K_L | 15.77 GiB | 16,931,077,632 | 4.975 | — | bartowski |
| Q5_K_S | 17.59 GiB | 18,884,206,080 | 5.549 | — | bartowski |
| Q5_K_S | 17.59 GiB | 18,884,206,336 | 5.549 | — | legraphista |
KV cache by context
| Context | KV cache (f16)● | Flat formula | Overstated by | Full / windowed / recurrent |
|---|---|---|---|---|
| 4,096 | 1.44 GiB | 1.44 GiB | — | 23 / 23 / 0 |
| 8,192 | 2.25 GiB | 2.88 GiB | 1.28× | 23 / 23 / 0 |
| 16,384 | 3.68 GiB | 5.75 GiB | 1.56× | 23 / 23 / 0 |
| 32,768 | 6.56 GiB | 11.50 GiB | 1.75× | 23 / 23 / 0 |
| 65,536 | 12.31 GiB | 23.00 GiB | 1.87× | 23 / 23 / 0 |
| 131,072 | 23.81 GiB | 46.00 GiB | 1.93× | 23 / 23 / 0 |
23 of 46 layers cache only a 4,096-token window rather than the full context, on a period of 2. Figures assume the default configuration; --swa-full disables the saving entirely.
Compare with
Will it run on your card?
Why other calculators give a different number
A parameters × bits ÷ 8 estimate puts Q4_K_M at roughly 14.26 GiB. The real file is 15.50 GiB, because a quantization is a mixture and some tensors are always kept at higher precision. The larger discrepancy is the cache: a flat formula gives 11.50 GiB at 32K context where the real figure is 6.56 GiB, because most of this model's layers cache a fixed window rather than the whole context.
Architecture
Questions people ask
- How much VRAM does gemma-2-27b-it need?
- Q4_K_M is exactly 16,645,381,632 bytes (15.50 GiB) in weights. Add the KV cache, which depends on your context length, plus roughly half a gigabyte of runtime overhead.
- How large is gemma-2-27b-it's KV cache?
- 6.56 GiB at 32K context with an f16 cache, computed per layer. Quantizing the cache to q8_0 roughly halves it, which is often the difference between a context length fitting and not.
- Which quantization of gemma-2-27b-it should I use?
- Q4_K_M is the usual default. Pick the largest quantization that fits your card at the context you actually need — the table above gives exact sizes for every one published.