// NVIDIA Nemotron · Text LLM
Llama-3_1-Nemotron-Ultra-253B-v1: VRAM & local deployment
253.4B parameters. About 172 GB at 4-bit and 560 GB at BF16 with one 8K-token request.
released 2025-04-07licence: Commercial with conditionsmemory figures are estimates
01Specs
| Publisher | NVIDIA · nvidia |
|---|---|
| Family / series | NVIDIA Nemotron · Llama-3_1-Nemotron-Ultra |
| Type | Text LLM (text-generation) |
| Parameters | 253.4B Source: counted from official safetensors weights |
| Context length | 128K tokens (131,072)max_position_embeddings in config.json |
| Architecture | 162 layers (64 full-attention) · GQA-NAS |
| Released weights | BF16 · 507 GBdownload |
| Licence | nvidia-open-model-license · Commercial with conditionsCommercial use allowed under the publisher’s own licence terms (user caps, acceptable-use policy, attribution or region limits). Read it before shipping. |
| Released | 2025-04-07 (Hugging Face repo created) |
02How much VRAM it needs (estimate)
Total = weights + 10% + 0.5GB overhead + KV cache for one request (FP16 KV). More concurrent users multiply the KV column.
| Precision | Weights | Total @ 8K | Total @ 32K | Total @ 128K | Smallest GPU | Mac |
|---|---|---|---|---|---|---|
| BF16 / FP16 (original) | 507 GB | 560 GB | 567 GB | 592 GB | 8 × H100 (640GB) | — |
| FP8 / INT8 / Q8_0 | 269 GB | 299 GB | 305 GB | 331 GB | 4 × RTX PRO 6000 (384GB) | Mac 512GB |
| 4-bit (Q4_K_M / AWQ / GPTQ-Int4) | 154 GB | 172 GB | 178 GB | 204 GB | 4 × RTX PRO 6000 (384GB) | Mac 256GB |
KV cache per request: 8K 2.1 GB · 32K 8.6 GB · 128K 34.4 GB
Bits per weight: BF16 16, FP8 8.5, 4-bit 4.85. “Fits” = total ≤ 90% of memory; Mac GPU can use ~2/3 of unified memory (≤36GB) or ~3/4 (larger). For MoE, all experts must be in memory, so size by total parameters. Method →
03How to run it
Only runtimes the publisher or the runtime’s official library names for this model.
- vLLM — mentioned in the official model card
- Transformers — mentioned in the official model card
04Official repositories & quantised builds
2 official repo(s) from nvidia.
05Other NVIDIA Nemotron models
All 62 →| Model | Params | 4-bit total | Released |
|---|---|---|---|
| NVIDIA-Nemotron-Labs-Dory1.0-4B-BF16 | 3.98B | 3.6 GB | 2026-10-16 |
| Nemotron-3.5-Rerank-8B-BF16 | 8.38B | 6.1 GB | 2026-10-15 |
| NVIDIA-Nemotron-3.5-Super-VL-120B-A12B-BF16 | 124.5B / 12B | 83.5 GB | 2026-10-12 |
| NVIDIA-Nemotron-3.5-Bolt-74B-A9B-BF16 | 74.9B / 9B | 50.4 GB | 2026-10-09 |
| Nemotron-3.5-Embed-1B-BF16 | 1.55B | 1.5 GB | 2026-10-07 |
| Nemotron-3.5-Embed-8B-BF16 | 8.38B | 6.1 GB | 2026-10-07 |
| Nemotron-3.5-Parse | 631M | 1.1 GB | 2026-09-03 |
| Nemotron-3-Labs-Ultra-Math-RL | 550B / 55B | 367 GB | 2026-09-02 |
06Sources
Data checked 2025-10-15. Parameters, context and licence are copied from the official repository; memory figures are our estimates.