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THE MODEL, IN DETAIL / NVIDIA

Nemotron 3.5 Lightning (free)

nvidia/nemotron-3.5-lightning:freeAccess not documentedReasoningUnspecified source configuration configuration

NVIDIA Nemotron 3.5 Lightning is an open mixture-of-experts model from NVIDIA, with 3B active parameters out of 30B total. It is suited for high-throughput agentic workloads and specialized tasks that...

OpenRouter
Source-linked model intelligenceCatalog added 11 Aug 2026Specifications observed 28 Oct 2026

Specifications and providers describe NVIDIA: Nemotron 3.5 Lightning (free). Evaluation scores retain the exact Unspecified source configuration configuration.

Published evaluations

0

Results connected

Context window

1M

65.5K max output tokens

Input price

$0

USD / million input tokens

Output price

$0

USD / million output tokens

Inference providers

1

1 provider routes observed

Measured output speed

—

No model-level measurement

01 / PERFORMANCE

A clearer view of capability.

Read the score, understand the context, and explore where this model sits among its peers.

Performance fingerprint

Individual published accuracy scores · not a composite index

At least three published accuracy scores are needed for this view.

Performance meets price

Source-aligned model comparison

A shared benchmark and documented prices are needed for this comparison.

In good company

Published model comparisons

No published measurements in this snapshot.

0 models in the source cohort. Showing selected nearby models. Evaluation settings can differ.

Evidence, by task.

Coverage is not a capability score.

0published results
0 evaluation sources
ReasoningAwaiting evidence
CodingAwaiting evidence
MathematicsAwaiting evidence
VisionAwaiting evidence
AgenticAwaiting evidence
Long contextAwaiting evidence

Documented features, task evaluations, and preference rankings describe different things. Missing coverage does not imply a model cannot perform a task.

Explore our methodology

02 / BENCHMARK EXPLORER

The numbers behind the model.

Original results, exact versions, and a direct path to the evidence behind every score.

0 published results

Percentage-based evaluations will appear here when published.

0 percentage-based evaluations. Each benchmark measures a different task; compare results within the same evaluation and protocol.

03 / COST & VALUE

Know what your workload costs.

Explore token prices, see where the spend goes, and model a workload of your own.

Input$0per million tokens
Output$0per million tokens
Cache read—per million tokens
Cache write—per million tokens

Workload cost calculator

Change the numbers. See the trade-offs.

Cache-read pricing is not documented for this selection.

Token estimate only. Excludes cache writes, tools, and other provider fees. Actual token usage and provider limits vary.

Your estimated spend

1,000 requests · 11M tokens

$0estimated total
Uncached input$0
Cached input$0
Output$0
Per request$0
Without cache discount$0
Estimated cache savings$0

04 / INFERENCE NETWORK

One model. Different ways to run it.

Compare inference routes by price, context, quantization, and reported availability.

1 providers · 1 routes
Provider routes for Nemotron 3.5 Lightning (free), observed 28 Oct 2026
Provider / routeInput / MOutput / MCache / MContextOutput limitSpeedLatencyAvailability · 1dRates
NNvidiaNVFP4$0$0—1M65.5K——97.71%

Snapshot observed 28 Oct 2026. Speed and latency are the reported 30-minute median when available. This is a dated snapshot, not live monitoring.

Provider price comparison

USD per million tokens · input and output rates

InputOutput
Nvidianvfp4
Input
$0
Output
$0

Reported availability

Provider availability over the selected observation window

Nvidia · NVFP497.71%

Output speed

Reported 30-minute p50 · tokens per second

No provider throughput measurements were returned in this snapshot.

Response latency

Reported 30-minute p50 · seconds

No provider latency measurements were returned in this snapshot.

Context by provider

Actual route limits can differ from the catalog maximum

Nvidia · NVFP41M

05 / CAPABILITIES & MODALITIES

What goes in. What comes out.

A map of documented interfaces and API features, separate from benchmark performance.

INPUT MODALITIES

Text
Nemotron 3.5 Lightning (free)Reasoning supported

OUTPUT MODALITIES

Text

Feature support

Listed catalog API parameters and documented pricing features

ReasoningSupported
Tool callingSupported
Tool choiceSupported
Structured outputsNot listed
Response formatNot listed
Reasoning detailsSupported
Seed controlSupported
Stop sequencesNot listed
Prompt cachingNot documented
TemperatureSupported

Room to work

Context capacity and completion limits

1Mtotal context tokens
Context window
65.5Kmax output

Output tokens share the total context budget. The maximum completion length is a separate limit, and individual provider routes may have smaller limits.

Catalog context
1,000,000 tokens
Maximum output
65,536 tokens
Top-provider context
1,000,000 tokens

Features vary by route

Check the provider before depending on a specific API feature.

API feature support by provider
Provider routeReasoningToolsStructured outputResponse formatImplicit caching
Nvidia · NVFP4SupportedSupportedNot listedNot listedNot listed

06 / UNDER THE HOOD

The complete specification sheet.

Exact identities, model architecture, limits, and the defaults that shape a request.

Identity & architecture

Developer
NVIDIA
Exact identity
nvidia/nemotron-3.5-lightning:free
Subject
Model Configuration
Access
unknown
License
Not disclosed
Parameters
Not disclosed
Tokenizer
Other
Instruction format
Not disclosed

Reasoning & controls

Reasoning
Supported
Mandatory reasoning
No
Reasoning by default
Not documented
Published configuration
Unspecified source configuration
Supported reasoning efforts
Not documented
Default reasoning effort
Not disclosed
API parameters
8
Provider moderation
No
Quantization variants
nvfp4

Dates & limits

Catalog added
11 Aug 2026
Knowledge cutoff
Not disclosed
Catalog expiration
Not documented
Specifications observed
28 Oct 2026
Providers observed
28 Oct 2026
Request limits
Provider-specific / not supplied
Canonical catalog ID
nvidia/nemotron-3.5-lightning-20260807

API parameters & defaults

Availability is catalog-wide. Defaults can vary across providers.

include_reasoningSupported · default not supplied
max_tokensSupported · default not supplied
reasoningSupported · default not supplied
seedSupported · default not supplied
temperatureSupported · default not supplied
tool_choiceSupported · default not supplied
toolsSupported · default not supplied
top_pSupported · default not supplied

07 / BUILD WITH THIS MODEL

From exploration to your first request.

Use the documented catalog identifier and keep your API key in an environment variable.

Make an API request

const response = await fetch(
  "https://openrouter.ai/api/v1/chat/completions",
  {
    method: "POST",
    headers: {
      Authorization: `Bearer ${process.env.OPENROUTER_API_KEY}`,
      "Content-Type": "application/json",
    },
    body: JSON.stringify({
      "model": "nvidia/nemotron-3.5-lightning:free",
      "messages": [
        {
          "role": "user",
          "content": "Explain the trade-offs in this design."
        }
      ],
      "reasoning": {
        "effort": "unspecified source configuration"
      }
    }),
  },
);
if (!response.ok) throw new Error(`HTTP ${response.status}`);
const data = await response.json();
console.log(data.choices[0].message.content);

08 / PROVENANCE & HISTORY

Every number has a story.

Follow the source, check the observation date, and distinguish published results from model specifications.

The observation trail

Recorded events, in chronological order

Added to the model catalog

Catalog creation date, as recorded by OpenRouter.

Provider routes observed

1 inference routes in this snapshot.

Model specifications observed

Catalog pricing, limits, and supported parameters captured.

Observation dates describe when data was captured. They do not represent newly run evaluations or continuous performance monitoring.

Published observation ledger

Historical evidence, with source and version preserved.

No published benchmark observations for this selection. Published preference rankings appear separately above.

09 / A FEW MORE DETAILS

Questions worth asking.

Quick answers, drawn from this model’s connected specifications.

How much does Nemotron 3.5 Lightning (free) cost?

Catalog starting rates are $0 per million input tokens and $0 per million output tokens. Compare provider routes and service tiers above for their specific prices.

How much context can it handle?

1,000,000 tokens in the catalog context window. The catalog lists a maximum of 65,536 completion tokens. Provider limits can differ.

Does it support tools and structured output?

Tool calling: listed as supported. Structured outputs: not listed. See the provider feature matrix for route-specific differences.

How should I interpret these benchmark results?

Read the benchmark name, exact version, metric, source, and model configuration together. Different evaluation settings can change the result. Preference ratings and source-defined composite indices remain separate from task accuracy.

Are these prices and provider measurements live?

This page uses dated source snapshots. Catalog data was observed on 28 Oct 2026. Provider routes were observed on 28 Oct 2026. Missing measurements are not estimated or treated as zero.

KEEP EXPLORING

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