GPT-OSS 20B needs ~18.6 GB VRAM. NVIDIA L4 24GB has 24.0 GB. With Q4_K_M quantization, expect ~34 tok/s.
Operating mode
Interactive favors responsiveness, while light API and scale-out lean harder on serving readiness. The fit stays the same, but the recommendation lens changes.
Current mode
Balanced
Balanced for general local use. Keeps the ranking neutral across personal and serving workflows.
Select quantization to explore
Fit status
Runs well
Decode
33.7 tok/s
TTFT
5746 ms
Safe context
52K
Memory
18.6 GB / 24.0 GB
This setup is broadly balanced for this model.
No major red flags
This recommendation has enough memory headroom and acceptable estimated speed for the selected workload.
| Workload | Grade | Fit | Decode | TTFT | Context |
|---|---|---|---|---|---|
| Chat | S | Runs well | 33.7 tok/s | 3134 ms | 52K |
| Coding | S | Runs well | 33.7 tok/s | 5746 ms | 52K |
| Agentic Coding | S | Tight fit | 33.7 tok/s | 8358 ms | 52K |
| Reasoning | S | Runs well | 33.7 tok/s | 6791 ms | 52K |
| RAG | S | Tight fit | 33.7 tok/s | 10448 ms | 52K |
How GPT-OSS 20B (21B params) fits at each quantization level on NVIDIA L4 24GB (24.0 GB usable).
| Quant | Bits | VRAM | Quality | Fit |
|---|---|---|---|---|
Q2_K | 2 | 8.2 GB | Low | S86 |
Q3_K_S | 3 | 10.3 GB | Low | S88 |
NVFP4 | 4 |
Copy-paste commands to run GPT-OSS 20B on your machine.
Run
ollama run gpt-ossYour hardware
| Model | Params | Grade | Decode | Capabilities |
|---|---|---|---|---|
| 30.5B | S | 21.2 tok/s | ||
| 27B | S | 8.9 tok/s |
Yes, NVIDIA L4 24GB can run GPT-OSS 20B with a S grade (Runs well). Expected decode speed: 33.7 tok/s.
GPT-OSS 20B (21B parameters) requires approximately 18.6 GB of memory with Q4_K_M quantization.
The recommended quantization for GPT-OSS 20B is Q4_K_M, which balances quality and memory efficiency.
On NVIDIA L4 24GB, GPT-OSS 20B achieves approximately 33.7 tokens per second decode speed with a time-to-first-token of 5746ms using Q4_K_M quantization.
For coding workloads, GPT-OSS 20B on NVIDIA L4 24GB receives a S grade with 33.7 tok/s and 52K context.
On NVIDIA L4 24GB, GPT-OSS 20B can safely use up to 52K tokens of context. The model's official context limit is 128K, but available memory constrains the safe maximum.
Paste this snippet into any page to show a live fit card.
<iframe src="https://willitrunai.com/embed/gpt-oss-20b-on-l4-24gb" width="400" height="180" frameborder="0" style="border:none;border-radius:12px;overflow:hidden;" title="Will It Run AI — fit result"></iframe>
Preview:
11.8 GB |
| Medium |
| S89 |
Q4_K_M | 4 | 12.8 GB | Medium | S89 |
Q5_K_M | 5 | 15.1 GB | High | S88 |
Q6_KBest for your GPU | 6 | 17.2 GB | High | S88 |
Q8_0 | 8 | 22.5 GB | Very High | F0 |
F16 | 16 | 43.1 GB | Maximum | F0 |
| 27B | S | 6.2 tok/s |
| 35B | A | 13.6 tok/s |
| 30B | S | 30.5 tok/s |