NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4

---

library_name: transformers license: other license_name: openmdw-1.1 license_link: https://openmdw.ai/license/1-1/ pipeline_tag: text-generation language:

• en
• es
• fr
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• it
• ja tags:
• nvidia
• pytorch
• nemotron-3.5 track_downloads: true

---

NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4

Model Summary

Total Parameters	30B (3B active)
Architecture	MoE - Mamba-2 + MoE + Attention hybrid
Context Length	Up to 1M tokens
Single-GPU Deployment	1× DGX Spark (GB10) or 1× H100
Supported Hardware	NVIDIA Blackwell (DGX Spark / GB10, GB200, GeForce RTX 5090); NVIDIA Hopper (H100, H200); NVIDIA Ampere via W4A16
Supported Languages	English (and coding languages), Spanish, French, German, Italian, Japanese
Speculative Decoding	DSpark for low-concurrency Data Centre and DGX Spark Workflows — Read more below, also provided are MTP (Multi-Token Prediction) and DFlash
Recommended Sampling	Temperature 1.0, Top_P 0.95
Best For	Long-running autonomous agents, sub-agent workhorse deployments, and efficient local inference on personal hardware
License	OpenMDW License Agreement, version 1.1
Release Date	August 11, 2026

Hardware Matrix

Hardware	Stored precision	Compute path	MoE backend (per recipe)	Native FP4 tensor-core path	Validated context
Blackwell — GB200	NVFP4	FP4	default	Yes	1M (default)
Blackwell — DGX Spark (GB10)	NVFP4	W4A16	marlin	No — runs via Marlin	1M (default)
Blackwell — GeForce RTX 5090	NVFP4	confirm	no recipe published	Hardware: yes	confirm
Hopper — H100 / H200	NVFP4	W4A16	humming (max-tput) / default	No — Hopper has no FP4 tensor cores	1M (default)
Ampere — A100, etc.	NVFP4	W4A16	humming	No	1M (default)

Model Overview

Model Developer: NVIDIA Corporation

Model Dates: December 2025 - May 2026

Data Freshness:

• The pre-training data has a cutoff date of September 2025.
• The post-training data has a cutoff date of May 2026.

What is Nemotron?

NVIDIA Nemotron™ is a family of open models with open weights, training data, and recipes, delivering leading efficiency and accuracy for building specialized AI agents.

Description

NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4 is a large language model (LLM) trained by NVIDIA.

The model employs a hybrid Mixture-of-Experts architecture, utilizing interleaved Mamba-2 and MoE layers, along with select Attention layers. The Lightning 3.5 model is released alongside a number of speculative decoding methods for faster text generation. The model has 3B active parameters and 30B parameters in total.

This model is ready for commercial use.

Quick Start

To get quickly started on DGX Spark (GB10) you can use the following command.

Grab the model:

export MODEL_CKPT=nvidia/NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4
export DSPARK_CKPT=nvidia/NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4-DSpark

Run it with vLLM — this recipe uses DSpark speculative decoding, tuned for DGX Spark. (vLLM version: vllm/vllm-openai:v0.27.1)

vllm serve --model $MODEL_CKPT \
  --moe-backend marlin \
  --kv-cache-dtype fp8 \
  --enable-prefix-caching \
  --gpu-memory-utilization 0.85 \
  --speculative_config.num_speculative_tokens 3 \
  --mamba-backend flashinfer \
  --mamba-cache-mode align \
  --reasoning-parser nemotron_v3 \
  --speculative_config.model $DSPARK_CKPT \
  --tool-call-parser qwen3_coder \
  --enable-auto-tool-choice

Validated context: 1M tokens (default).

For more details on how to deploy and use the model — see the Quick Start Guide below!

License/Terms of Use

Governing Download Terms: Use of this model is governed by the OpenMDW-1.1 model license.

Benchmarks

Reasoning Benchmark Evaluations

We evaluated our model on the following benchmarks:

Task	Nemotron-3.5-Lightning-30B-A3B-BF16	Nemotron-3.5-Lightning-30B-A3B-NVFP4
General Knowledge
MMLU Pro	81.94	81.62
AA-Omniscience	17.50	16.63
Reasoning
GPQA Diamond (no tools)	75.44	75.57
HLE (text-only, no tools)	11.72	10.47
SciCode	32.60	31.38
Coding & Agentic
SWE-bench Verified	51.56	52.80
SWE-bench Multilingual	39.33	36.47
Terminal-Bench 2.1	24.58	23.46
PinchBench	85.37	83.43
BrowseComp	36.97	36.81
τ³-bench (Banking)	9.28	9.48
GDPval-AA-V2	832	865
Instruction Following
IFBench (loose)	71.88	72.88
Long Context
AA-LCR	52.00	49.19

Accuracy numbers measured by NVIDIA under a consistent harness (NeMo Gym / Nemo Evaluator SDK); they may differ from vendors' self-reported numbers.

For reproducibility, the evaluation recipes, installation instructions, and commands for NVIDIA Nemotron 3.5 Lightning were collected and published in NeMo Gym. The reported results cover the release evaluation suite, including knowledge and reasoning, instruction following, coding, agentic, tool-use, and long-context. Most evaluations use NeMo Gym-native harnesses while a small subset, including SWE-Bench and Terminal-Bench, used NeMo Evaluator natively. The published recipes specify the benchmark-specific containers, prompts, inference parameters, parser configurations, and scoring settings used to produce the results.

These numbers were measured with and apply to the official NVFP4 checkpoint

Agentic Coding Benchmarks

Additional harness-level coding-agent results for SWE-Bench Verified and Terminal-Bench 2.1 are shown below.

Deployment Geography: Global

Use Case

NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4 is a general purpose reasoning and chat model intended to be used in English and coding languages. Other non-English languages (Spanish, French, German, Italian, Japanese) are also supported. Intended for developers designing AI Agent systems, chatbots, RAG systems, and other AI-powered applications. Also suitable for typical instruction-following tasks.

Release Date

Hugging Face — 08/11/2026

Model Architecture

• Architecture Type: Mixture-of-Experts Hybrid (Mamba + Transformer)
• Network Architecture: Nemotron-3-Lightning + Multi-Token Prediction (MTP)
• Number of model parameters: 30B Total / 3B Active

Model Design

The model was pre-trained with over 20T tokens and supports up to 1M context length. The pre-training phase used an NVFP4 recipe. The model includes Multi-Token Prediction (MTP) layers, which predict multiple future tokens to provide richer training signals.

Training Methodology

Stage 1: Pre-Training

• NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4 model was pre-trained using an NVFP4 recipe with crawled and synthetic code, math, science, and general knowledge data.
• Software used for pre-training: Megatron-LM

Stage 2: Continued Pre-Training for Multi-Token Prediction (MTP)

• The model underwent a continued pre-training phase to train its Multi-Token Prediction (MTP) layers. In this stage, MTP heads learn to predict multiple future tokens, providing richer training signals to the base model. This phase aligns the MTP layers with the base model's distribution.

Stage 3: Supervised Fine-Tuning

• The model was further fine-tuned on synthetic code, math, science, tool calling, instruction following, structured outputs, and general knowledge data. This stage incorporated data designed to support long-range retrieval and multi-document aggregation.

Stage 4: Reinforcement Learning

• The model underwent multi-environment reinforcement learning using GRPO (Group Relative Policy Optimization) across math, code, science, instruction following, multi-step tool use, multi-turn conversations, and structured output environments. It utilized an asynchronous RL architecture that decouples training from inference and leverages MTP to accelerate rollout generation.
• Software used for reinforcement learning: NeMo RL, NeMo Gym

Stage 5: Post-training Quantization (PTQ)

• We performed post-training quantization (PTQ) with Nvidia Model Optimizer using the following recipe: Four Over Six NVFP4 (a variant of static MSE calibration) W4A16 on routed and shared experts, FP8 per-tensor dynamic scales on mamba in_proj/out_proj and KV cache. We used a subset of the Nemotron Ultra validation set for calibration with 1000 samples at 32k token length.

NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4 is a result of the above work.

Input

• Input Type(s): Text
• Input Format(s): String
• Input Parameters: One-Dimensional (1D): Sequences
• Other Properties Related to Input: Maximum context length up to 1M tokens. Supported languages include English, Spanish, French, German, Italian, and Japanese.

Output

• Output Type(s): Text
• Output Format: String
• Output Parameters: One-Dimensional (1D): Sequences
• Other Properties Related to Output: Maximum context length up to 1M tokens

Our AI models are designed and/or optimized to run on NVIDIA GPU-accelerated systems. By leveraging NVIDIA's hardware (e.g. GPU cores) and software frameworks (e.g., CUDA libraries), the model achieves faster training and inference times compared to CPU-only solutions.

Software Integration

• Runtime Engine(s): PyTorch
• Supported Hardware Microarchitecture Compatibility: NVIDIA Blackwell; NVIDIA Hopper (NVFP4 / W4A16); NVIDIA Ampere (W4A16)
• Preferred/Supported Operating System(s): Linux

The integration of foundation and fine-tuned models into AI systems requires additional testing using use-case-specific data to ensure safe and effective deployment. Following the V-model methodology, iterative testing and validation at both unit and system levels are essential to mitigate risks, meet technical and functional requirements, and ensure compliance with safety and ethical standards before deployment.

Model Version(s)

• GA (08/11/2026)

Quick Start Guide

Choose your deployment

Setup & goal	Recommended path	Speculative decoding	Validated context
DGX Spark (GB10)	vLLM + DSpark	DSpark (num_speculative_tokens 3)	1M
1× H100 — max throughput (batch)	vLLM, no spec decoding (humming backend)	None	1M (default)
1× H100 — interactive (40+ TPS/user)	vLLM + DSpark, concurrency ≤ 128	DSpark (num_speculative_tokens 3)	1M (default)
8× H100 — long context	vLLM, TP8 + expert parallel	None	1M
1× GB200	vLLM + DSpark	DSpark (num_speculative_tokens 5)	1M (default)
Ampere (A100, etc.)	vLLM, W4A16 kernels	None	1M (default)
Local — llama.cpp	llama-server ...	—	~40K example, VRAM-bound
Local — Ollama / LM Studio / Jan…	ollama run nemotron-3.5-lightning	built-in	varies

All deployment snippets below assume:

export MODEL_CKPT=nvidia/NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4

And for DSpark:

export DSPARK_CKPT=nvidia/NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4-DSpark

Speculative Decoding Strategies

Lightning 3.5 ships with two external draft models for speculative decoding as well as MTP (Multi-Token Prediction). While DSpark is our recommended default (see Choose your deployment), some workloads are better served without speculative decoding, or by DFlash or MTP:

• DSpark: A semi-autoregressive speculative-decoding drafter that proposes a whole block of candidate tokens in a single forward pass from a parallel backbone. This is recommended for DGX Spark, as well as low-concurrency data centre deployments.
• DFlash: A speculative-decoding drafter that uses a lightweight block-diffusion model to generate an entire draft block in one forward pass.
• MTP: A modeling technique that trains the network to predict several future tokens at each position instead of only the next one.

DSpark is the recommended default for DGX Spark and latency-sensitive, low-concurrency serving. For maximum-throughput batch serving on H100, no speculative decoding is fastest.

vLLM

For more indepth instructions on how to deploy through vLLM, head here

• vLLM version: vllm/vllm-openai:v0.27.1

1x DGX Spark (GB10)

vllm serve --model $MODEL_CKPT \
  --moe-backend marlin \
  --kv-cache-dtype fp8 \
  --enable-prefix-caching \
  --gpu-memory-utilization 0.85 \
  --speculative_config.num_speculative_tokens 3 \
  --mamba-backend flashinfer \
  --mamba-cache-mode align \
  --reasoning-parser nemotron_v3 \
  --speculative_config.model $DSPARK_CKPT \
  --tool-call-parser qwen3_coder \
  --enable-auto-tool-choice

Validated context: 1M tokens (default).

1x H100 (max throughput)

For max throughput deployments, use the following configuration, no speculative decoding strategy is best for this serving configuration, and due to memory constraints the Mamba cache dtype is set as FP16:

vllm serve --model $MODEL_CKPT \
    --max-num-seqs 256 \
    --max-num-batched-tokens 16384 \
    --enable-prefix-caching \
    --async-scheduling \
    --mamba-backend flashinfer \
    --moe-backend humming \
    --linear-backend humming \
    --mamba-ssu-algorithm horizontal \
    --mamba-cache-mode align \
    --mamba-ssm-cache-dtype float16 \
    --enable-mamba-cache-stochastic-rounding \
    --mamba-cache-philox-rounds 5 \
    --reasoning-parser nemotron_v3 \
    --tool-call-parser qwen3_coder \
    --enable-auto-tool-choice

Validated context: 1M tokens (default).

1x H100 (interactive)

For interactive usage scenarios (achieving 40+ TPS/User) use a lower concurrency (<=128) with DSpark:

vllm serve --model $MODEL_CKPT \
    --max-num-seqs 128 \
    --enable-prefix-caching \
    --async-scheduling \
    --speculative_config.model $DSPARK_CKPT \
    --speculative_config.num_speculative_tokens 3 \
    --mamba-backend flashinfer \
    --mamba-ssm-cache-dtype float16 \
    --mamba-cache-mode align \
    --enable-mamba-cache-stochastic-rounding \
    --mamba-cache-philox-rounds 5 \
    --reasoning-parser nemotron_v3 \
    --tool-call-parser qwen3_coder \
    --enable-auto-tool-choice

Validated context: 1M tokens, served by default. Lower --max-model-len for more KV-cache headroom at high concurrency.

8x H100 (vLLM)

For long-context, multi-GPU serving (TP8 with expert parallelism):

vllm serve --model $MODEL_CKPT \
    --mamba-backend flashinfer \
    --async-scheduling \
    --enable-prefix-caching \
    --mamba-cache-mode align \
    --enable-expert-parallel \
    --tensor-parallel-size 8 \
    --reasoning-parser nemotron_v3 \
    --tool-call-parser qwen3_coder \
    --enable-auto-tool-choice

Validated context: 1M tokens (TP8 + expert parallel).

1x GB200 (vLLM)

vllm serve --model $MODEL_CKPT \
    --max-num-batched-tokens 10240 \
    --no-enable-prefix-caching \
    --async-scheduling \
    --speculative_config.model $DSPARK_CKPT \
    --speculative_config.num_speculative_tokens 5 \
    --mamba-backend flashinfer \
    --reasoning-parser nemotron_v3 \
    --tool-call-parser qwen3_coder \
    --enable-auto-tool-choice

Validated context: 1M tokens (default).

W4A16 (vLLM)

The same checkpoint also serves via W4A16 kernels, extending coverage to Ampere-class GPUs, like the A100 80GB:

vllm serve --model nvidia/NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4 \
    --moe-backend humming \
    --linear-backend humming \
    --max-num-seqs 256 \
    --max-num-batched-tokens 32768 \
    --enable-prefix-caching \
    --async-scheduling \
    --quantization modelopt_fp4 \
    --mamba-backend flashinfer \
    --mamba-cache-mode align \
    --mamba-ssu-algorithm simple \
    --reasoning-parser nemotron_v3 \
    --tool-call-parser qwen3_coder \
    --enable-auto-tool-choice

Validated context: 1M tokens (default)

• Context Length: The H100 and GB200 snippets above serve the model's full 1M-token context window by default. If you're memory-constrained — or want more KV-cache headroom at high concurrency — lower --max-model-len to match your workload.

TensorRT-LLM

For more indepth instructions on how to deploy through TensorRT-LLM, head here

Container: nvcr.io/nvidia/tensorrt-llm/release:1.3.0rc24

1x H100 (TensorRT-LLM)

cat > nemotron-35-lightning-nvfp4-mtp.yaml << EOF
kv_cache_config:
  dtype: fp8
  enable_block_reuse: false
  mamba_state_config:
     periodic_snapshot_interval: 8192
  free_gpu_memory_fraction: 0.8
  mamba_ssm_cache_dtype: float16
  mamba_ssm_stochastic_rounding: true
  mamba_ssm_philox_rounds: 5
moe_config:
   backend: MARLIN
nvfp4_gemm_config:
  allowed_backends: [marlin, cutlass, cublaslt, cuda_core]
cuda_graph_config:
    enable_padding: true
    max_batch_size: 8
speculative_config:
  decoding_type: MTP
  max_draft_len: 3
  allow_advanced_sampling: true
enable_chunked_prefill: true
num_postprocess_workers: 4
print_iter_log: true
stream_interval: 10
disable_overlap_scheduler: false
EOF

trtllm-serve \
$MODEL_CKPT \
--max_batch_size 8 \
--max_num_tokens 8192 \
--reasoning_parser nemotron-v3 \
--tool_parser qwen3_coder \
--config nemotron-35-lightning-nvfp4-mtp.yaml

Validated context: 1M tokens by default; lower --max_seq_len if memory-constrained.

SGLang

For more indepth instructions on how to deploy through SGLang, head here or the SGLang cookbook

• Container: lmsysorg/sglang:dev-nemotron3-5-lightning

1x B200

Balanced — no speculative decoding:

sglang serve \
    --model-path $MODEL_CKPT \
    --mamba-backend flashinfer \
    --mamba-ssm-dtype float16 \
    --enable-mamba-cache-stochastic-rounding \
    --mamba-cache-philox-rounds 5 \
    --mem-fraction-static 0.85 \
    --cuda-graph-max-bs-decode 16 \
    --reasoning-parser nemotron_3 \
    --tool-call-parser qwen3_coder \
    --port 8000

1x H100

On Hopper the NVFP4 weights run through W4A16 kernels; the flashinfer Mamba backend is not required (FA3 target attention is selected by default):

sglang serve \
    --model-path $MODEL_CKPT \
    --mamba-ssm-dtype float16 \
    --mem-fraction-static 0.85 \
    --cuda-graph-max-bs-decode 16 \
    --reasoning-parser nemotron_3 \
    --tool-call-parser qwen3_coder \
    --port 8000

1x DGX Spark (GB10)

Smaller memory budget — --mem-fraction-static and --cuda-graph-max-bs-decode are lowered accordingly:

sglang serve \
    --model-path $MODEL_CKPT \
    --mamba-ssm-dtype float16 \
    --mem-fraction-static 0.78 \
    --cuda-graph-max-bs-decode 4 \
    --reasoning-parser nemotron_3 \
    --tool-call-parser qwen3_coder \
    --port 8000

Speculative decoding

The blocks above run the balanced baseline. To enable one of the speculative decoding strategies described above, append the matching flags to any command:

MTP — the draft head is embedded in the target checkpoint (no separate download):

    --speculative-algorithm EAGLE \
    --speculative-draft-model-path $MODEL_CKPT \
    --speculative-num-steps 5 \
    --speculative-eagle-topk 1 \
    --speculative-num-draft-tokens 6

DFlash — separate draft model (--speculative-dflash-block-size is 6 on B200, 4 on H100 / DGX Spark):

    --speculative-algorithm DFLASH \
    --speculative-draft-model-path nvidia/NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4-DFlash \
    --speculative-dflash-block-size 6

DSpark — separate draft model:

    --speculative-algorithm DSPARK \
    --speculative-draft-model-path $DSPARK_CKPT \
    --speculative-dspark-block-size 3

• Context length: The commands above serve the model's full context window by default. Set --context-length to a smaller value if you're memory-constrained or want more KV-cache headroom at higher concurrency.

Local AI (RTX 5090, DGX Spark, and RTX 6000 Pro)

The following recipes are validated and provided by our fantastic partners.

Ollama

• ollama version: 0.32.9

For local, single-command use, Nemotron 3.5 Lightning is on Ollama, with tool-calling and thinking enabled.

ollama run nemotron-3.5-lightning

Validated context: Ollama will dynamically set context based on available VRAM (under 24GB -> 4K, 24-48GB -> 32K, 48GB+ -> 256K). You can use /set parameter num_ctx DESIRED_CONTEXT_LENGTH which may result in CPU offloading for higher context limits.

llama.cpp

Official GGUF weights: ggml-org/NVIDIA-Nemotron-3.5-Lightning-30B-A3B-GGUF.

• llama.cpp version: https://github.com/ggml-org/llama.cpp/releases/latest

Simplest start:

llama-server -hf ggml-org/NVIDIA-Nemotron-3.5-Lightning-30B-A3B-GGUF \
  --port 8000

Full server recipe with recommended sampling:

llama-server \
  -hf ggml-org/NVIDIA-Nemotron-3.5-Lightning-30B-A3B-GGUF:Q4_K_M \
  --temp 1.0 --top-p 0.95 \
  -np 1 \
  -c 40960 \
  --port 8000 \
  -ngl 99 \
  -fa on \
  --jinja \
  --no-webui \
  --fit off

Validated context: the examples set -c 40960 (~40K); raise it as VRAM allows.

LM Studio

You can also run Nemotron 3.5 Lightning 30B A3B through LM Studio from this resource!

API Client

The examples below use the OpenAI-compatible client and work with any of the serving backends above. All backends serve on port 8000 (vLLM and TRT-LLM by default; SGLang via --port 8000), so the base_url works as-is. Recommended sampling settings are Temperature 1.0 and Top_P 0.95.

The vLLM snippets above pass the checkpoint to --model $MODEL_CKPT, and vLLM registers the model under that same identifier (nvidia/NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4) — none of the commands set --served-model-name. For the other backends — or if you add a --served-model-name of your own — copy the identifier returned by GET /v1/models into MODEL below.

from openai import OpenAI
client = OpenAI(base_url="http://localhost:8000/v1", api_key="EMPTY")
MODEL = "nvidia/NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4"

Lightning 3.5 exposes reasoning control through chat-template kwargs: thinking enabled (the default), and thinking disabled for direct answers.

Reasoning ON / OFF and streaming examples: Click to expand!

Reasoning ON (default)

response = client.chat.completions.create(
    model=MODEL,
    messages=[{"role": "user", "content": "Write a haiku about GPUs"}],
    max_tokens=16000,
    temperature=1.0,
    top_p=0.95,
    extra_body={"chat_template_kwargs": {"enable_thinking": True}}
)
print(response.choices[0].message.content)

Reasoning OFF

response = client.chat.completions.create(
    model=MODEL,
    messages=[{"role": "user", "content": "What is the capital of Japan?"}],
    max_tokens=16000,
    temperature=1.0,
    top_p=0.95,
    extra_body={"chat_template_kwargs": {"enable_thinking": False}}
)
print(response.choices[0].message.content)

Streaming

stream = client.chat.completions.create(
    model=MODEL,
    messages=[{"role": "user", "content": "Explain speculative decoding in two sentences"}],
    max_tokens=16000,
    temperature=1.0,
    top_p=0.95,
    stream=True,
)
for chunk in stream:
    print(chunk.choices[0].delta.content or "", end="", flush=True)

Tool Calling

The TRT-LLM snippet above already launches with the required parsers (--reasoning_parser nemotron-v3 --tool_parser qwen3_coder). For vLLM, add the following to any serve command above:

    --enable-auto-tool-choice \
    --tool-call-parser qwen3_coder \
    --reasoning-parser nemotron_v3

NOTE: For coding agents, add extra_body={"chat_template_kwargs": {"force_nonempty_content": True}} to the API call, as shown below.

tools = [{
    "type": "function",
    "function": {
        "name": "get_weather",
        "description": "Get the current weather for a city",
        "parameters": {
            "type": "object",
            "properties": {"city": {"type": "string"}},
            "required": ["city"],
        },
    },
}]

response = client.chat.completions.create(
    model=MODEL,
    messages=[{"role": "user", "content": "What's the weather in Santa Clara?"}],
    tools=tools,
    max_tokens=16000,
    temperature=1.0,
    top_p=0.95,
    extra_body={"chat_template_kwargs": {"force_nonempty_content": True}},
)
print(response.choices[0].message.tool_calls)

Training, Testing, and Evaluation Datasets

Training

Data Modality: Text Training Data Size: More than 20 Trillion Tokens Dataset partition: Training [100%], testing [0%], validation [0%] Time period for training data collection: 2013 to December 2025 Time period for testing data collection: 2013 to December 2025 Time period for validation data collection: 2013 to December 2025 Data Collection Method by dataset: Hybrid: Automated, Manually-Collected, Synthetic Labeling Method by dataset: Hybrid: Automated, Manually-Labeled, Synthetic

NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4 is pre-trained on a large corpus of high-quality curated and synthetically-generated data. It is trained in the English language, as well as 19 other spoken languages and 43 programming languages. Our sources cover a variety of document types such as: webpages, dialogue, articles, and other written materials. The corpus spans domains including legal, math, science, finance, and more. We also include a small portion of question-answering, and alignment style data to improve model accuracy. The model was pre-trained for more than 20 trillion tokens.

The post-training corpus for NVIDIA-Nemotron-3.5-Lightning-30B-A3B-NVFP4 consists of high-quality curated and synthetically-generated data. Primary languages used for post-training include English, French, German, Italian, Japanese, Spanish, and Chinese.

These datasets, such as FinePDFs, EssentialWeb, HotpotQA, SQuAD, and HelpSteer3, do not collectively or exhaustively represent all demographic groups (and proportionally therein). For instance, these datasets do not contain explicit mentions of demographic classes such as age, gender, or ethnicity in 64-99% of samples, depending on the source. In the subset where such terms are present, document-based datasets (FinePDFs and EssentialWeb) contain representational skews, such as references to "male" outnumbering those to "female", and mentions of "White" as the most frequent among ethnic identifiers (comprising 43-44% of ethnicity mentions). To mitigate these imbalances, we recommend considering evaluation techniques such as bias audits, fine-tuning with demographically balanced datasets, and mitigation strategies like counterfactual data augmentation to align with the desired model behavior. This evaluation used a 3,000-sample subset per dataset, identified as the optimal threshold for maximizing embedder accuracy.

During post-training, we generate synthetic data by distilling trajectories, solutions, and translations from strong teacher models and agent systems, often grounded in real tasks or documents and aggressively filtered for quality. For math, code, and science, we start from curated problem sets and use open source permissive models such as GPT-OSS-120B to produce step-by-step reasoning traces, candidate solutions, best-of-n selection traces, and verified CUDA kernels. For long-context and science, we build synthe