Tools / LLM GPU calculator / L40S
What LLMs fit on an NVIDIA L40S?
Which of 22 open LLMs fit one L40S, and how many it takes for the rest, at FP16, FP8 and 4-bit.
Short answer
One NVIDIA L40S (48 GB) runs 15 of the 22 open LLMs sized here at 4-bit, 11 at FP8 and 5 at FP16, for one user at an 8K context. At FP8: Llama 3.1 8B, Qwen3 8B, Qwen3 14B, Phi-4 14B, gpt-oss-20b, LFM2.5-24B-A2B, Mistral Small 3.2 24B, Gemma 3 27B, Qwen3-30B-A3B, Qwen3 32B and Qwen2.5 32B. The largest that fits one GPU is Kolibri-1 (78.1B parameters), at 4-bit. Within one 8-GPU server, tensor parallelism runs every model except Llama 3.1 405B, Llama 4 Maverick, Qwen3-235B-A22B, DeepSeek-V3 / R1 and GLM-5.3 at FP8. Llama 3.3 70B takes 4 GPUs (tensor parallel 4) at FP16 and 2 GPUs (tensor parallel 2) at FP8.
Updated . One user, 8K context, KV cache at FP16, plus 10% headroom for activations and the runtime.
Every model on the L40S
| Model | FP16/BF16 | FP8 | 4-bit (INT4) |
|---|---|---|---|
| Llama 3.1 8B | 1 GPU19 GB | 1 GPU10 GB | 1 GPU6.1 GB |
| Qwen3 8B | 1 GPU20 GB | 1 GPU10 GB | 1 GPU6.3 GB |
| Qwen3 14B | 1 GPU34 GB | 1 GPU18 GB | 1 GPU11 GB |
| Phi-4 14B | 1 GPU35 GB | 1 GPU18 GB | 1 GPU11 GB |
| gpt-oss-20b | 1 GPU47 GB | 1 GPU23 GB | 1 GPU13 GB |
| LFM2.5-24B-A2B | 2 GPUs · TP254 GB | 1 GPU27 GB | 1 GPU15 GB |
| Mistral Small 3.2 24B | 2 GPUs · TP255 GB | 1 GPU28 GB | 1 GPU16 GB |
| Gemma 3 27B | 2 GPUs · TP262 GB | 1 GPU32 GB | 1 GPU18 GB |
| Qwen3-30B-A3B | 2 GPUs · TP269 GB | 1 GPU35 GB | 1 GPU20 GB |
| Qwen3 32B | 2 GPUs · TP275 GB | 1 GPU39 GB | 1 GPU22 GB |
| Qwen2.5 32B | 2 GPUs · TP275 GB | 1 GPU39 GB | 1 GPU22 GB |
| Mixtral 8x7B | 4 GPUs · TP4105 GB | 2 GPUs · TP253 GB | 1 GPU30 GB |
| Llama 3.3 70B | 4 GPUs · TP4160 GB | 2 GPUs · TP281 GB | 1 GPU46 GB |
| Qwen2.5 72B | 4 GPUs · TP4165 GB | 2 GPUs · TP284 GB | 1 GPU47 GB |
| Kolibri-1 | 4 GPUs · TP4174 GB | 2 GPUs · TP287 GB | 1 GPU48 GB |
| Llama 4 Scout | 8 GPUs · TP8243 GB | 4 GPUs · TP4122 GB | 2 GPUs · TP268 GB |
| gpt-oss-120b | 8 GPUs · TP8260 GB | 4 GPUs · TP4130 GB | 2 GPUs · TP272 GB |
| Qwen3-235B-A22B | Multi-server524 GB | Multi-server263 GB | 4 GPUs · TP4145 GB |
| Llama 4 Maverick | Multi-server894 GB | Multi-server448 GB | 8 GPUs · TP8247 GB |
| Llama 3.1 405B | Multi-server907 GB | Multi-server456 GB | 8 GPUs · TP8253 GB |
| DeepSeek-V3 / R1 | Multi-server1,492 GB | Multi-server746 GB | Multi-server411 GB |
| GLM-5.3 | Multi-server1,654 GB | Multi-server827 GB | Multi-server455 GB |
Counts use a tensor-parallel size (TP) that divides the model's attention heads, within one 8-GPU server. Below each count is the memory needed: (weights + KV cache) ÷ 0.9. Capacity only: speed depends on memory bandwidth and the serving stack.
Memory is step one. Throughput, latency, power and the network decide the real build.
Size my actual workloadL40S specifications
- Memory
- 48 GB GDDR6
- Memory bandwidth
- 864 GB/s
- Typical system
- PCIe server
- Counted as
- Tensor parallel within one 8-GPU server (vLLM style)
Configurations and pricing: NVIDIA L40S in the catalog.
Questions about the L40S
What LLMs can run on an NVIDIA L40S?
For one user at an 8K context, these fit one L40S. At 4-bit: every model except Llama 3.1 405B, Llama 4 Scout, Llama 4 Maverick, Qwen3-235B-A22B, DeepSeek-V3 / R1, gpt-oss-120b and GLM-5.3. At FP8: Llama 3.1 8B, Qwen3 8B, Qwen3 14B, Phi-4 14B, gpt-oss-20b, LFM2.5-24B-A2B, Mistral Small 3.2 24B, Gemma 3 27B, Qwen3-30B-A3B, Qwen3 32B and Qwen2.5 32B. At FP16/BF16: Llama 3.1 8B, Qwen3 8B, Qwen3 14B, Phi-4 14B and gpt-oss-20b.
What is the largest LLM an L40S can run?
Of the models sized here, for one user at an 8K context: at 4-bit, Kolibri-1 (78.1B parameters, 48 GB); at FP8, Qwen3 32B (32.8B parameters, 39 GB); at FP16, gpt-oss-20b (20.9B parameters, 47 GB). Mixture-of-experts models count every expert, because all of them must be in memory.
How many NVIDIA L40S GPUs does Llama 3.3 70B need?
For one user at an 8K context it needs 160 GB at FP16/BF16, 81 GB at FP8 and 46 GB at 4-bit: 4 GPUs (tensor parallel 4) at FP16, 2 GPUs (tensor parallel 2) at FP8 and 1 GPU at 4-bit.
Can an NVIDIA L40S run DeepSeek-V3 / R1?
Not on one GPU: with all 671B parameters resident it needs 746 GB at FP8 and 411 GB at 4-bit for one user at an 8K context. That is more than one 8-GPU server (at least 16 GPUs) at FP8 and more than one 8-GPU server (at least 9 GPUs) at 4-bit.
Other GPUs
- RTX PRO 6000 Workstation
- RTX PRO 6000 Server
- H100 SXM
- H100 NVL
- H200
- B200
- B300
- Instinct MI300X
- Instinct MI355X
- RTX 3090
- RTX 4090
- RTX 5090
- 96 GB Mac Studio
- 256 GB Mac Studio
- 512 GB Mac Studio
Different context length, more users, or a model that isn’t listed? The LLM GPU calculator sizes any Hugging Face model for any of these GPUs.
Need to deploy private AI?
We design it, validate it, source it, deploy it and help run it.
Give us your workload, users, budget and timeline. Within 48 hours we'll give you a validated cloud/on-prem architecture, BOM, expected costs and sourcing options.