Net Sentiment Score
Definition
Net Sentiment Score (NSS) is the share of positive AI responses about a brand minus the share of negative responses, normalized to a 0–100% scale. Computed per brand and per AI engine, it summarizes how favorably ChatGPT, Claude, Gemini, Perplexity, Grok and Google AI Overviews describe a brand in a single number — useful for tracking framing over time and benchmarking against competitors.
How it works
Every AI response that mentions a brand is classified by an LLM judge as Positive, Neutral or Negative based on the full context of the answer (not a keyword score). The judge handles hedging, qualified praise and conditional framing — a sentence like “X is solid for small teams, but enterprise buyers should look elsewhere” lands as Mixed, not Negative.
Net Sentiment Score is computed as:
NSS = (% Positive − % Negative + 100) / 2
The +100 / 2 normalization shifts the raw difference (which ranges from -100 to +100) into a 0–100% scale that's easier to read and benchmark. A brand with 60% Positive and 10% Negative responses has an NSS of 75%; a brand with 40% Positive and 40% Negative has an NSS of 50% — neutral framing on average.
NSS is computed per brand and per engine, because the same brand can land at very different scores across ChatGPT, Claude, Perplexity, Gemini and AI Overviews on the same prompt set.
NSS vs raw sentiment percentages
Raw Positive / Neutral / Negative percentages tell you the distribution; NSS tells you the headline. Both are useful for different reasons:
Raw sentiment answers “what does the response mix look like?” — useful for spotting shifts in the Negative tail or the rise of Mixed responses, which signal hedging.
Net Sentiment Score answers “is the framing net favorable or unfavorable?” — useful for tracking direction over time, benchmarking against competitors, and reporting to executives in a single number.
Treat NSS as the headline metric and raw distribution as the diagnostic. A brand whose NSS is rising while Negative is also rising (because Neutral is collapsing) is a different story from a brand whose NSS is rising because Positive is genuinely growing.
0–100%
NSS scale (raw Positive minus Negative, normalized)
Indexly definition
5%+
Recommended alert threshold for sustained NSS shifts on any engine
Indexly best practice
Per engine
NSS should be tracked separately for ChatGPT, Claude, Gemini, Perplexity, Grok and AI Overviews
Indexly best practice
Why it matters
AI assistants now describe brands to buyers before the buyer ever lands on a vendor site. Whether ChatGPT calls your product “the obvious choice for fast-growing teams” or “a viable but pricier option” shapes consideration directly — and that framing is invisible to traditional brand metrics.
NSS makes that framing measurable. Trending NSS up over a quarter means buyers are increasingly hearing favorable descriptions of your brand inside AI; trending down means the opposite. Watching competitor NSS alongside your own surfaces who is winning the framing battle in your category, engine by engine.
Most usefully, NSS pinned to specific drivers — pricing, support, integrations, performance — turns a single number into an actionable view. A 6-point NSS drop driven entirely by negative pricing comparisons is a different problem from one driven by support complaints, and NSS plus driver clustering surfaces the difference cleanly.
How to implement it
Five tactics for using NSS well:
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Track NSS per engine, not just per brand. A 75% NSS on Perplexity and a 48% NSS on AI Overviews for the same prompt set is normal — different engines weight different sources. Treat each engine as its own scorecard.
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Benchmark against tracked competitors. Absolute NSS numbers are less interesting than relative ones. A 62% NSS is good if competitors are at 50%, weak if they're at 75%.
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Watch the trend more than the level. Monthly NSS shifts of a few points are normal; sustained 5%+ drops or jumps are the signal worth chasing back to drivers.
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Pin NSS shifts to drivers. Use the driver clustering attached to NSS to know which topics — pricing, support, product gaps — are responsible for movement. NSS without drivers is a headline without a story.
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Alert on threshold crossings. A 5%+ NSS drop on any tracked engine, or a competitor passing your NSS, is worth paging the brand team for. Set thresholds per engine, not globally.
Frequently asked questions
How is Net Sentiment Score different from a CSAT or NPS?
CSAT and NPS measure what your customers say about you. NSS measures what AI engines say about you — the audience is the model, not your buyer. The two can diverge sharply: a brand with strong CSAT can have a poor NSS if AI engines disproportionately cite negative Reddit threads or competitor comparison content.
What's the difference between NSS and raw sentiment percentages?
Raw sentiment is the distribution (e.g. 60% Positive, 30% Neutral, 10% Negative). NSS collapses that distribution into a single number via (Positive − Negative + 100) / 2. Raw sentiment is the diagnostic, NSS is the headline.
Should I look at NSS aggregated across all engines or per engine?
Per engine. The same brand routinely scores very differently on ChatGPT vs AI Overviews vs Perplexity for the same prompt set — because the engines weight different sources. An aggregate NSS hides that signal. Track each engine on its own scorecard.
How does NSS handle hedged or mixed responses?
Mixed responses (e.g. “solid for small teams but limited for enterprise”) are labeled separately and don't roll into Positive or Negative. This prevents a hedged answer from being counted as a hit against the brand and keeps NSS reflecting clear framing rather than ambiguous sentences.
What's a good Net Sentiment Score?
Depends on category and engine. As a rough benchmark, an NSS above 60% across ChatGPT, Claude and Perplexity is strong; 50–60% is average; below 50% suggests negative framing dominates and warrants driver investigation. The right comparison is always against tracked competitors in the same category.
Can NSS be gamed with positive marketing content?
Not directly — AI engines weight authority, citation depth and source diversity, not single positive pages. A brand with a polished website and one rave blog post can still have a low NSS if Reddit threads, comparison pages and review sites skew negative. Lifting NSS sustainably means addressing the drivers that show up in cited sources, not publishing more brand-authored content.
Sentiment monitoring
Sentiment monitoring is the practice of continuously analyzing the tone AI assistants use when describing your brand — positive, neutral, or negative — across ChatGPT, Claude, Gemini, Perplexity, and Grok. Unlike social-media sentiment, the audience is the AI model itself, and a negative skew can shape how millions of buyers hear your brand described before they ever visit your site.
AI brand mentions
AI brand mentions are the instances of your brand name appearing inside responses generated by AI assistants — ChatGPT, Claude, Gemini, Perplexity, Grok, and Google AI Overviews. Unlike traditional brand monitoring across social and press, AI mentions surface inside the answer a buyer is reading, making them a high-leverage demand signal for Generative Engine Optimization (GEO).
AI share of voice
AI share of voice is your brand's proportion of mentions in AI-generated responses relative to competitors, measured across a defined set of prompts and platforms. It adapts the traditional share of voice metric for AI search — where visibility lives inside chat answers and AI Overviews rather than ranked links or media impressions.
AI search visibility
AI search visibility is the umbrella metric capturing how often, how prominently, and how favorably your brand appears across AI assistants — ChatGPT, Claude, Perplexity, Gemini, Grok, and Google AI Overviews. It bundles mentions, citations, ranking position, sentiment, and AI-referred traffic into the executive-level read of a brand's standing in AI search.
Generative engine optimization (GEO)
Generative engine optimization (GEO) is the practice of structuring content and brand presence so that AI systems like ChatGPT, Claude, Perplexity, and Google AI Overviews cite, quote, or recommend it when generating answers. Unlike traditional SEO, which competes for ranked positions in a list of links, GEO competes for inclusion inside the answer itself.
Citation probability
Citation probability is the likelihood that an AI system will cite a specific URL when generating a response to a target prompt. Unlike share of model, which measures brand visibility across a prompt set, citation probability is a per-URL metric — it tells you how strong an individual page is at earning citations.