Custom instructions are not your voice
ChatGPT's custom instructions capture about 5 surface-level preferences. ScriptGrain analyses 45 measured reference points from your real writing: the unconscious patterns that make your voice yours and nobody else's.
What ChatGPT custom instructions capture
Roughly five self-reported preferences. You describe your style; the AI guesses the rest.
- Tone (formal/casual)
- Response length preference
- Communication style
- Preferred language
- Custom instructions text
What custom instructions cannot capture
- Vocabulary analysis
- Sentence structure patterns
- Punctuation habits
- Rhetorical patterns
- Humour style detection
- Function word analysis
- Cadence & rhythm
- Opening/closing patterns
- Argument structure
- Confidence vs hedging
What a ScriptGrain voice profile measures
45 reference points extracted from writing you have already published (30 shown here). Your writing speaks for itself; we measure the patterns.
- Vocabulary diversity index
- Preferred words & filler phrases
- Sentence length variance
- Complexity preference
- Clause ordering
- Parenthetical & dash frequency
- Formality score (0-10)
- Humour register detection
- Emotional expressiveness
- Confidence vs hedging ratio
- Opening & closing style
- Metaphor usage rate
- Argument structure
- Comma density & exclamation rate
- Ellipsis & semicolon usage
- Article & pronoun distribution
- Discourse markers
- Specificity level
- Anecdote & analogy detection
- Rhythm pattern (punchy/flowing)
- Paragraph length preference
- Power sentence position
- Structural signatures
- Contraction frequency
- Rare word rate
- Word length distribution
- Repetition as emphasis
- Capitalisation quirks
- List preference style
- Audience adaptation detection
The profile spans eight layers: lexical choices, sentence syntax, tone and register, rhetorical structure, punctuation and formatting, function-word patterns, content patterns, and cadence quirks. Most of these are habits writers cannot describe about themselves, which is exactly why asking a model to "write like me" falls short.
Questions
How is ScriptGrain different from ChatGPT custom instructions?
ChatGPT custom instructions capture roughly five self-reported surface preferences: tone, response length, communication style, preferred language, and a free-text instruction box. ScriptGrain measures 45 reference points extracted from writing you have actually published, including the unconscious markers (function-word frequency, punctuation cadence, clause ordering) that custom instructions cannot capture at all.
What are the 45 measured reference points?
The profile spans eight layers: lexical choices (vocabulary diversity, preferred words, rare-word rate), sentence syntax (length variance, complexity, clause ordering), tone and register (formality, humour register, hedging), rhetorical structure (opening style, argument structure), punctuation and formatting habits, function-word patterns, content patterns, and cadence quirks.
Can I see my voice profile before paying?
Yes. The Free plan includes one voice profile and one writing analysis covering all 45 reference points, with no card required. Generating new content in that voice is the paid step, from £12/month.
What writing do I need to provide?
Writing you have already done: paste text, upload files, or import from a URL. As few as one piece works, and 3,000+ words across several samples gives the best results.
Weighing it against another tool? See the honest comparisons, or measure your style first with the free style analysis tool.
