How Naturable finds AI writing
Naturable's free checker uses no AI at all. It relies on deterministic rules — the same kind of pattern-matching a spell-checker uses — so it's instant, private, and costs nothing to run. Here's exactly what happens when you hit Check.
1. Pattern catalogue (33 tells)
Naturable uses a catalogue of 33 patterns drawn from Wikipedia's Signs of AI writing guide. The current free engine checks the deterministic and structural subset; semantic patterns are labelled for review instead of pretending a regular expression can understand meaning. Each implemented match is highlighted, explained, and paired with guidance.
- Vocabulary tells — over-used LLM words like delve, testament, landscape, leverage, robust, seamless.
- Cadence tells — "It's not just X, it's Y", the rule of three, manufactured punchlines.
- Filler & hedging — "in order to", "due to the fact that", stacked hedges.
- Structure tells — em-dash overuse, emoji, bold overuse, Title Case headings.
- Chatbot leftovers — "Great question!", "I hope this helps", cutoff disclaimers.
Current implementation: 22 deterministic phrase and style rules, plus structural checks for heading and boldface patterns. Semantic-only patterns remain manual review items while Pro is being tested.
2. Sentence-rhythm analysis (burstiness)
AI writing tends to be uniform: sentences hover around the same length with the same structure. Human writing has burstiness — it alternates short, punchy sentences with longer, winding ones. Naturable measures this as the coefficient of variation of your sentence lengths:
burstiness = standard deviation of sentence length ÷ mean sentence length
This is pure arithmetic — no model required. Higher variation reads more human, and we surface it as your Sentence rhythm score.
3. The scores
Two headline numbers, both heuristic:
- Human score (0–100) — the inverse of an "AI-tell index" built from tell density, the count of strong tells, and a penalty for low burstiness. Higher is cleaner.
- Sentence rhythm — your burstiness, scaled to 0–100.
These are guidance, not a verdict. Naturable is a writing-quality tool, not a detector, and no tool can promise a specific outcome against any third-party checker.
4. Fixing: rules first, AI when needed
Fixes come in two tiers:
- Quick fix (free) — deterministic replacements the rules can make safely: cutting em-dashes, removing emoji and chatbot chatter, "in order to" → "to", straight quotes, and so on.
- AI rewrite (Pro, testing) — planned for semantic tells rules cannot safely rewrite. Pricing is being tested and the product is not yet open.
Privacy
The current free checker runs entirely in your browser. Your text is never uploaded. Planned Pro processing is still being tested and is not yet open. See our Privacy Policy.