How do you write a tone of voice guide?
How to write a tone of voice guide
A tone of voice guide works when it is specific enough to settle an argument about a sentence. "Friendly, expert, human" cannot do that — two writers will read those words and produce different paragraphs, both defensible. A usable guide states measurable rules (sentence length range, contractions yes or no, whether you address the reader as "you", which punctuation is house style, banned phrases) and pairs each rule with a before/after example taken from your own published writing.
The fastest way to write one is backwards: collect the eight to ten pieces your team agrees sound right, measure what they have in common, and write the guide from those numbers. A guide derived from real examples gets followed because it describes what the best writers on the team already do; a guide written from adjectives in a workshop gets ignored by week three.
- Derive the guide from writing you already like — don't invent it in a workshop.
- Every rule needs a before/after example, or it is not a rule.
- Include the banned list: the phrases that make people close the tab.
- Enforcement is a checklist at review time, not a PDF in a shared drive.
What goes in it
Six sections are enough. First, who is talking and to whom — the relationship, not the persona. Second, the measurable rules: sentence length range, paragraph length, contraction policy, person and address, punctuation house style, and whether numbers and specifics are required in claims. Third, five before/after pairs from your own writing. Fourth, the banned list: the phrases, openings and structures you never publish. Fifth, register variations, because support replies, release notes and the careers page cannot share one voice. Sixth, how to resolve disagreement — who decides, and what the tie-break rule is.
Keep it under four pages. A guide that cannot be read in ten minutes will be read by nobody, and length is usually a symptom of the author padding around rules they were unwilling to make concrete.
The banned list does most of the work
Positive instructions are hard to follow; prohibitions are easy. Most teams get further with a page of things never to write than with a page of adjectives. Typical entries: "we're thrilled to announce", "in today's fast-paced world", "delve", "unlock", "game-changer", rhetorical questions as an opening, a closing paragraph that summarises the piece the reader just read, and any sentence that could appear on a competitor's site unchanged.
This section is also the one that keeps AI-assisted drafts in line, because those phrases are precisely what a model reaches for when it has no constraints. If your guide names them, a reviewer catches them in seconds.
Make it enforceable
A guide with no enforcement point is decoration. Put the rules into the place where writing is reviewed: a short checklist in the pull request or doc template with five questions taken straight from the guide. Then measure the published output once a quarter against the same features you used to write it — if the average sentence length has crept from 15 to 24, the guide has quietly stopped being true and the drift needs a decision, not a reprimand.
For teams using AI drafting, the enforcement point moves earlier: the rules become the constraints on generation, so the first draft already sits inside the guide instead of being edited into it afterwards.
Deriving the numbers from your own writing
StyleMimic's style analyzer is a shortcut for the measurement step: paste the pieces your team agrees on and it returns sentence length and variance, contraction rate, punctuation habits, hedging density and repeated openers — the raw material for the rules section, in numbers you can put straight in the document.
Save it as a named profile and every draft your team writes with StyleMimic is measured against the same guide, with a match score that shows how close each draft landed. That is the difference between a voice document and a voice that survives contact with a deadline.
Questions
How long should a tone of voice guide be?
Two to four pages. Anything longer is usually adjectives padding out rules the author avoided making concrete, and it will not be read.
Should each channel have its own voice?
One voice, several registers. Support replies, product copy and long-form articles differ in length, formality and contraction rate, but the banned list and the underlying relationship with the reader stay the same across all of them.
How do we keep AI drafts inside the guide?
Turn the guide's measurable rules into the constraints the draft is generated against, rather than editing a generic draft into shape afterwards. That is what a measured style profile does.
Written for a specific job? For brands & teams