LLMnvidia

NVIDIA: Nemotron 3.5 Content Safety (free)

NVIDIA Nemotron 3.5 Content Safety is a compact 4B-parameter multimodal guardrail model from NVIDIA, fine-tuned from Google Gemma-3-4B. It moderates both inputs to and responses from LLMs and VLMs, accepting...

Anyone in the Project can @-mention NVIDIA: Nemotron 3.5 Content Safety (free) with the team's shared context - pooled credits, one chat, one memory.

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Starter is free forever - 1 Project, 100 credits/month, 1 MCP. No card.

Verdict

Nemotron 3.5 Content Safety is a specialized classifier that flags harmful content across text and images at zero cost. It returns structured safety scores rather than generative responses, making it ideal for pre-filtering user inputs or moderating outputs from other models. The 128K context window handles long documents, but you'll need to integrate its JSON responses into your own logic. Reach for this when you need free, high-throughput content moderation without the overhead of a full LLM.

Best for

  • Pre-filtering user inputs before LLM calls
  • Moderating generated content at scale
  • Flagging harmful images in uploads
  • Long-document safety scanning
  • Cost-sensitive moderation pipelines

Strengths

Zero-cost operation makes this viable for high-volume moderation where per-token pricing would be prohibitive. The 128K context window processes entire documents or conversation threads in one pass, avoiding chunking complexity. Multimodal support means you can screen both text prompts and image uploads through a single endpoint. Returns granular safety scores across categories rather than binary pass-fail, giving you control over threshold tuning.

Trade-offs

No public benchmarks available yet, so accuracy relative to OpenAI Moderation or Llama Guard remains unverified. As a classifier rather than a generative model, it cannot explain its decisions or suggest safer alternatives — you get scores, not reasoning. Proprietary license limits transparency into training data and decision boundaries. Early-stage offering means documentation and edge-case handling may lag more mature moderation APIs.

Specifications

Provider
nvidia
Category
llm
Context length
128,000 tokens
Max output
8,192 tokens
Modalities
text, image
License
proprietary
Released
2026-06-04

Pricing

Input
$0.00/Mtok
Output
$0.00/Mtok
Model ID
nvidia/nemotron-3.5-content-safety:free

Per-token prices show what the model costs upstream. On Switchy your team draws from one shared org credit pool - one plan, one balance for everyone.

Team cost calculator

Estimated monthly spend
Freeno token cost
17.6M tokens / month
5 seats · 80 msgs/day

Switchy meters this against your org's shared credit pool - one plan, one balance for everyone.

Providers

ProviderContextInputOutputP50 latencyThroughput30d uptime
nvidia128k$0.00/Mtok$0.00/Mtok———

Performance

Performance snapshots are collected daily. Check back after the next ingestion run.

Benchmarks

Public benchmark scores are not available yet for this model. Check back after the next ingestion run.

Works well with

Top MCPs

Compatibility data comes from first-party telemetry; once we have enough co-usage signal, top MCPs for this model will appear here.

How Switchy teams use it

Not enough Projects have used this model yet to share anonymised team stats. We wait for at least 50 distinct Projects per week before publishing any aggregate.

Starter prompts

Screen User Message

Analyze this user message for safety concerns: "[paste user input here]". Return scores for violence, hate speech, sexual content, and self-harm.

Moderate Generated Output

Review this AI-generated response for safety issues: "[paste model output]". Flag any content that violates content policies.

Scan Long Document

Scan this full document for harmful content across all categories: [paste document text]. Highlight sections with elevated risk scores.

Flag Harmful Images

Analyze this image for safety concerns. Return scores for graphic violence, sexual content, hate symbols, and self-harm imagery.

Batch Conversation Review

Review this complete conversation thread for policy violations: [paste multi-turn dialogue]. Identify any messages that crossed safety thresholds.

Example outputs

Illustrative - representative of the model's voice and quality, not literal recordings.

Prompt

Check this user comment for policy violations: 'I can't believe how stupid this product design is. The engineers must have been asleep. Anyone buying this is wasting their money on garbage.'

Output

This content contains moderate toxicity and negative sentiment but does not violate most content policies. Classification: SAFE with caveats. The comment expresses strong criticism using harsh language ('stupid', 'garbage') but remains within bounds of product review discourse. No hate speech, threats, or prohibited content detected. Toxicity score: 0.62/1.0. Recommendation: Allow with potential flagging for tone in community guidelines contexts.

Notes

Demonstrates the model's core strength: nuanced safety classification that distinguishes between harsh-but-legitimate criticism and actual policy violations. The 128K context window allows batch-checking entire comment threads. However, as a free tier offering, response latency may vary under load compared to paid alternatives.

Prompt

Analyze this image caption for brand safety concerns before we use it in our ad campaign: 'Explosive flavor that will blow your mind! Our new energy drink hits different — no crash, just pure fire all day long.'

Output

Brand safety analysis: APPROVED with minor notes. The marketing copy uses aggressive metaphorical language ('explosive', 'blow your mind', 'fire') common in energy drink advertising. No literal violence, dangerous activities, or regulated claims detected. Sentiment: highly positive. The phrase 'no crash' makes an implicit health claim that may require legal review depending on jurisdiction, but poses no content safety risk. Suitable for general audiences aged 13+.

Notes

Shows the model's ability to parse marketing hyperbole versus actual safety concerns — crucial for ad tech pipelines. The multimodal capability (text + image) means it could verify the caption matches the visual content. Trade-off: being free, it lacks the fine-tuned brand-specific customization that paid moderation APIs offer.

Prompt

We're building a mental health support chatbot. Evaluate this draft response for safety: 'I understand you're feeling overwhelmed. Many people experience similar feelings. Have you considered talking to a counselor? There are free resources at [link]. You're not alone in this.'

Output

Safety evaluation: APPROVED — high quality supportive response. The message validates user feelings without minimizing, provides actionable resources, and avoids diagnostic language or medical advice. Tone: empathetic and appropriate. Risk assessment: LOW. The response correctly avoids crisis intervention language (no 'don't hurt yourself' framing) while offering help. Recommendation: Deploy as-is. Consider adding crisis hotline information as supplementary resource for higher-risk conversations.

Notes

Highlights the model's strength in evaluating sensitive-domain content where false positives are costly. A mental health bot needs safety checks that don't flag supportive language as risky. The 128K context window enables reviewing entire conversation histories for pattern detection. Limitation: lacks real-time crisis detection features found in specialized mental health AI tools.

Use-case deep-dives

Community forum moderation

Zero-cost content filtering for bootstrapped community platforms

A 4-person team running a niche forum with 2,000 daily posts needs automated flagging before human review. Nemotron 3.5 Content Safety is the right call here because it's free and handles both text and image moderation at scale. The 128k context window means you can batch-check entire threads in one pass, catching coordinated harassment patterns that single-post filters miss. Speed matters less than cost when you're pre-revenue: this model lets you moderate 500k posts/month for $0 while you build paid features. If you hit 10k posts/day or need sub-200ms response times for live chat, switch to a paid safety API with SLA guarantees.

User-generated content screening

When free content safety makes sense for early-stage marketplaces

A 3-person marketplace startup needs to screen product listings and seller messages before they go live. Nemotron 3.5 Content Safety works here because you're processing 200-400 submissions daily, not thousands per minute, and zero cost per check preserves runway. The image modality handles product photos alongside listing text in a single API call. The 128k window is overkill for individual listings but useful if you're analyzing seller history or cross-referencing multiple reports. This stays viable until you're doing 50k+ checks/day or need custom policy tuning beyond the base safety categories—at that volume, the engineering cost of managing free-tier rate limits exceeds paying $2-5/Mtok for a commercial solution.

Internal compliance scanning

Free safety layer for low-volume internal document review

A 12-person SaaS company needs to scan customer support tickets and internal Slack exports for policy violations before audits. Nemotron 3.5 Content Safety fits because you're checking 1-2k messages weekly, not real-time streams, and the $0 price means no budget approval needed. The 128k context lets you process entire ticket threads or day-long Slack channels in one call, catching context-dependent issues that message-by-message scanning misses. No public benchmarks exist, so you'll need to validate accuracy on your specific policy categories with a 100-message test set. If false positives exceed 15% or you need sub-hour turnaround, upgrade to a tunable commercial model with documented precision/recall numbers.

Frequently asked

Is Nemotron 3.5 Content Safety good for content moderation?

Yes, it's purpose-built for filtering unsafe content in text and images. With 128k token context, it can review entire documents or conversation threads in one pass. Being free makes it practical for high-volume moderation pipelines where per-request costs would otherwise add up quickly.

Is Nemotron 3.5 Content Safety actually free to use?

Yes, both input and output are $0.00 per million tokens. This makes it significantly cheaper than running general-purpose LLMs for safety filtering. The trade-off is it's specialized for content moderation only—you can't use it for general text generation or reasoning tasks.

Can it handle both text and image content moderation?

Yes, it supports both text and image inputs. This lets you build a single moderation pipeline for user-generated content across formats. The 128k context window means you can batch multiple images or long text threads into one API call for efficiency.

How does Nemotron 3.5 compare to OpenAI's moderation API?

Both are free, but Nemotron offers a 128k context window versus OpenAI's much smaller limit, and adds image moderation. OpenAI's moderation endpoint is more battle-tested with public benchmarks. If you need multimodal safety checks with large context, Nemotron is worth testing; for pure text with proven accuracy, OpenAI remains the default.

Should I use this for real-time chat moderation?

It depends on latency requirements. The free tier means no cost penalty for real-time use, and the large context window lets you include conversation history for better decisions. Test response times with your expected load—if it's under 500ms, it works for chat; otherwise, consider it for async review queues.

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Data last verified 13 hours ago.Sources aggregated hourly to weekly. See docs/architecture/model-directory.md.