AI Hallucination Risk Checker
How likely is your AI response to contain hallucinated facts?
Paste in what you know about an AI response and get a hallucination risk score. The tool weighs confidence level, query complexity, training data freshness, claim density, and whether sources were cited to tell you how hard you should verify before acting.
—
Send feedback
💡 Share your idea or report a problem
✓ Thanks! We'll take a look.
Learn more
How It Works
The formula, explained simply
When an AI model generates a response, it does not look anything up in a database — it predicts the next most plausible token based on patterns in its training data. That means a response can sound authoritative and specific while being entirely fabricated. The model does not know it is wrong. This is what researchers call a hallucination: a confident, fluent, false output.
The hallucination risk score works by stacking risk factors multiplicatively. It starts from the model's stated confidence level — a 15% base risk for the example inputs — then amplifies or shrinks that number based on how hard the question is, how fresh the relevant training data is, whether the model backed its claims with sources, and how densely packed the response is with specific assertions. Each factor applies independently as a multiplier, so a single bad factor can double the risk, and several bad factors compound aggressively.
The result is a single percentage that tells you where to focus your verification energy. A 5% score on a simple lookup with full citations means a quick sanity-check is probably enough. A score in the high or very high range on an expert topic with no sources means you should treat the AI output as a rough draft, not a conclusion, and verify each specific claim before acting on any of them.
When To Use This
Right tool, right situation
Use this tool before acting on any AI-generated content that includes specific factual claims — research summaries, medical or legal background, technical specifications, historical facts, or business data. It is especially useful when you are evaluating responses from a model you have not used before and do not have a calibrated sense of its reliability on the topic in question.
This tool is also the right sanity-check when you are in a time-pressured situation and need to decide how much verification effort to allocate. A low-risk score on a simple topic with current training and full citations means a quick read is probably sufficient. A very high risk score means you need to budget real time for verification — treat the AI output as raw material, not as a finished answer.
Do not rely on this tool when the cost of being wrong is extremely high — medical diagnoses, legal filings, safety-critical engineering decisions. In those contexts, no risk score is a substitute for domain-expert review. The score helps you triage your verification effort; it does not replace expert judgment. Similarly, this tool is not designed to evaluate AI-generated creative content, code, or opinion pieces where factual hallucination is less the concern than logical or stylistic quality.
Common Mistakes
Why results sometimes look wrong
Mistake 1 — Treating confidence score as a reliability guarantee. The confidence score is the model's self-assessment, not an external audit. Models are miscalibrated: they often express high confidence on topics where their training data was sparse or contradictory. A 95% confidence score on an expert-domain question with outdated training data still produces a meaningful risk contribution from the other multipliers. Never short-circuit the full calculation just because confidence is high.
Mistake 2 — Counting only obvious numerical claims. When counting factual claims, people tend to count statistics and dates while missing softer claims: named organizations, attributed quotes, procedural steps presented as definitive, and descriptions of how systems work. These are all hallucination targets. Undercounting claims artificially suppresses the density multiplier and understates the true risk.
Mistake 3 — Assuming citations mean verified facts. AI models can cite sources that do not exist, or that exist but do not say what the model claims they say. Selecting yes for citations reduces the risk multiplier because cited responses are somewhat more likely to be accurate — but it does not eliminate risk. If you are making a consequential decision, follow the actual URLs and read the actual sources, do not just note that citations were present.
The Math
Worked examples and deeper derivation
The formula follows a multiplicative chain. First, compute the base risk: Base Risk = 100 minus the confidence score. For the example with a confidence score of 85, the base risk is 15%.
Next, apply four independent multipliers in sequence. Complexity: Simple queries use a 0.8x multiplier; Moderate a 1.0x; Complex a 1.4x; Expert a 1.8x. Training recency: Current topics use 0.7x; Recent 1.0x; Outdated 1.5x; Unknown 1.2x. Citations: Provided sources use 0.6x; Partial 0.9x; None 1.2x.
Claim density is computed as factual claims divided by (response length divided by 100). The density multiplier equals 1 plus (density times 0.1), capped at 2x and floored at 1x. For the example, that yields a density multiplier of 1.2xx. The final formula is: Risk = Base Risk times Complexity times Recency times Citations times Density. The result is then capped between 0 and 100 for display. The example yields 16.2%.
Expert Unlock
The thing most explanations skip
The multiplicative structure of this formula means risk can technically exceed 100% before capping — a mathematical artifact that signals when multiple high-risk factors are stacked. The cap keeps the display interpretable, but practitioners should note that a capped score does not mean all risks are equal: a response that computes to 180% uncapped is categorically more concerning than one that computes to 65% uncapped, even though both display as very high risk. When the uncapped value matters, check the base risk and density multiplier sub-outputs to understand which factors are driving the score.
The density multiplier has a deliberate ceiling of 2x to prevent a single very dense paragraph from dominating the entire score. In practice, this means the formula treats extremely claim-dense responses the same as moderately dense ones once the cap is hit — which is a known simplification. In a real evaluation, a 20-claim response in 100 words deserves more scrutiny than the capped multiplier alone would suggest.
What does my AI hallucination risk score actually mean?
Need something this doesn't cover?
Suggest a tool — we'll build it →