Brand Voice: How to Define, Document and Defend the Way Your Company Sounds

Most brand voice guides could be swapped between companies without anyone noticing. Four or five adjectives, a paragraph about personality, perhaps a "we are / we are not" table. Friendly but not goofy. Confident but not arrogant. Human.

None of that is wrong. It just cannot settle an argument. When a writer and an editor disagree about one sentence on the pricing page, "friendly but professional" gives neither of them anything to point at. The most senior opinion wins, and over time the voice becomes whatever the last reviewer happened to prefer.

This guide takes a different position: a brand voice is only as useful as the decisions it helps you make about individual sentences. It covers what brand voice is, how to find the one you already have, how to write it down so a sentence can pass or fail against it, and how to stop it drifting once the guide exists.

We build software that checks website copy against a brand voice, so we have an obvious interest in voice guides that can be tested. You do not need our software to use anything here.

What brand voice is (and what it is not)

Brand voice is the pattern of choices a company makes whenever it writes: what it says, what it refuses to say, how certain it sounds, which words it reaches for, how much it assumes the reader knows and what kind of relationship it sets up with them.

Most of those are decisions, not adjectives. Two companies can both be "friendly" and sound nothing alike, because one is friendly the way a good GP is and the other is friendly the way a mate at the pub is. The adjective is the same. The decisions underneath it are different.

Three terms tend to get tangled together:

• Voice is the stable part: the beliefs, vocabulary and habits that should be recognisable on every page.
• Tone is how that voice adjusts to the situation. Mailchimp's style guide explains that its voice barely changes from day to day, while its tone shifts with the context and the reader's state of mind.
• Style is mechanics: spelling, capitalisation, punctuation, dates and numbers. It matters, but it is the easiest part to document and the least distinctive.

Most guides spend the most words on style because it is easy to write rules for. Voice is harder to pin down, and it is the part that actually separates one company from another.

Why adjectives fail as a voice guide

A HubSpot guide to brand voice notes that brand leaders most often start by writing down four or five adjectives. It is the default because adjectives feel like they capture something. The trouble starts when someone tries to use them.

Take "confident". Here are two sentences a confident brand might publish:

The most advanced brand voice platform on the market.

We check every sentence on the page against the voice you set. You decide what changes.

The first is confident the way a billboard is. The second is confident the way someone who knows their work is. A guide that only says "confident" approves both, and it probably nudges writers towards the first, because superlatives are the quickest way to sound sure of yourself.

An adjective describes the effect you want the reader to feel. A useful guide describes the choices that produce that effect. "Confident" becomes something closer to: make claims you can show, say what the product does before what it achieves, and do not use a superlative unless you can name the comparison. Now the first sentence fails, the second passes, and nobody has to argue about taste.

That is the test for the rest of this guide: can two people use this rule to agree on whether a specific sentence passes? If they cannot, the rule describes a mood rather than a voice.

Define: find the voice you already have

Very few companies start from a blank page. If you have been publishing for more than a few months, you already have a voice. It is just scattered, inconsistent and partly accidental.

Start by collecting evidence rather than aspirations:

• Pages the team agrees sound most like you. This is often the About page or a founder's launch post.
• Emails and support replies that customers responded well to.
• Language from sales calls and customer interviews, especially the words customers use for the problem rather than the words you use internally.
• Copy you dislike. It is often easier to say exactly what is wrong with a sentence than what is right with one.

Then look for patterns across the good material. How long are the sentences? Does it use "we" and "you"? How does it handle a claim: stated boldly, hedged, or backed with a specific? What does it explain, and what does it assume the reader already knows? Which words keep appearing, and which never do?

Write down what you find, and label it honestly. At this stage you have an inferred voice: a reading of what your copy does now, not a decision about what it should do. The distinction matters. An inference can capture bad habits as easily as good ones, and it cannot see beliefs the company holds but has never written down. Someone with authority over the brand needs to confirm, correct or reject each part before anyone treats it as the standard.

This is also the point to decide who the voice is for. Monzo's tone of voice guide is a useful model. It applies to everyone who writes at the company, from support chats and job ads to compliance policies, and Monzo has written openly about the trust problem behind it: if a bank says it is customer-focused but writes in jargon, customers will not believe it. Start with the reader and the relationship you want with them. The adjectives mostly follow.

Document: write a voice guide you can test sentences against

The job of a voice guide is not to describe your personality. It is to let someone who has never met your founder write a sentence you would publish, and to let an editor explain why a sentence is wrong without falling back on "it just doesn't feel like us".

Turn each principle into a rule with evidence

For every voice principle, write down five things:

1. The principle, in a few words.
2. What it looks like in a sentence, as an observable behaviour.
3. A passing example, ideally real copy.
4. A failing example, ideally real copy you have since fixed.
5. The exception: when the principle bends, and how far.

Here is one of Revisi's own principles in that format.

Principle: Name the work.

Looks like: Sentences say what the product or person actually does, with a recognisable object and action. Benefits follow the mechanism rather than replacing it.

Passes: Paste a page URL and see which sentences need another look.

Fails: Unlock the full potential of your brand's content.

Exception: A headline can lead with the outcome if the next line names the mechanism.

The exception is the line most guides leave out, and it is what stops a principle hardening into a ban. Rules without exceptions tend to be either ignored or applied so literally that the copy goes stiff.

Document vocabulary as swaps, not bans

A list of banned words is tempting and mostly useless on its own, because writers need to know what to say instead. The best public guides pair each word with a replacement.

Monzo's guide swaps formal banking language for everyday words, such as "help" instead of "assistance" and "card machine" instead of "terminal", and encourages verbs over nouns, so "we analysed" rather than "we conducted an analysis of". The GOV.UK style guide keeps a long list of words to avoid, each with a plainer alternative. For "facilitate", it asks writers to say specifically what they are doing, such as running a workshop.

For your own guide, split vocabulary into three groups:

• Our words. Terms you use deliberately and consistently, including product names and your name for the problem you solve.
• Swaps. Words you replace, with the replacement beside them.
• Watch words. Words that are sometimes fine but usually signal lazy writing, such as "powerful", "seamless" or "solution". These do not need a ban. They need a question: what specific thing is this word standing in for?

Consistency in "our words" matters more than most teams expect. If one page calls a feature a voice profile, another calls it a brand guide and the app calls it brand settings, readers will reasonably assume those are three different things.

Set rules for certainty and claims

Most voice guides skip this section, yet it is often where the voice actually lives. How sure does your brand sound, and what earns that certainty?

Decide, in writing:

• Whether you use superlatives, and what evidence you need first.
• How you describe results: specific numbers, ranges, examples, or not at all.
• How you hedge, whether with "may", "can" and "often" or with plain statements and the limits stated separately.
• What you will never claim. A financial brand might never promise a return. A software brand might never call anything "effortless".

A brand that states its limits plainly and backs claims with specifics usually sounds more confident than one relying on big adjectives, even though its sentences are quieter.

Map tone as ranges, not a fixed setting

Your voice should be recognisable everywhere. Your tone should not be identical everywhere. An error message, a price increase and a homepage headline need different amounts of warmth, humour and energy, even when they come from the same company.

The Nielsen Norman Group offers a practical way to document this. Its research describes tone along four dimensions: funny to serious, formal to casual, respectful to irreverent, and enthusiastic to matter-of-fact. In its testing, changing only the tone of otherwise matching website copy measurably changed how friendly, trustworthy and desirable people found the organisation.

Use those four dimensions to build a small tone map for the situations you write in most often:

The table does not need to be precise. Its job is to stop someone bringing launch-day energy to a billing problem, and to give an editor a shared reference when a message feels wrong for the moment.

Show whole pieces, not just sentences

Include a few complete examples as well: a homepage section, a support reply, an email. Voice lives partly in rhythm and structure, which single sentences cannot show. Before-and-after rewrites are especially useful because they teach the judgement behind the result.

Mailchimp's guide is worth reading for this reason. It does not just list traits; it explains trade-offs, including that clarity matters more than entertainment and that the brand prefers "the subtle over the noisy, the wry over the farcical". That is a real decision a writer can apply to a draft.

Keep it short enough to use

A voice guide nobody opens is worse than no guide, because it creates the impression the problem is solved. Put the principles, the tone map and the vocabulary swaps on one page someone can read in five minutes. Detailed style rules and long examples can sit in an appendix.

Defend: stop your voice drifting

Writing the guide is only the start. When Monzo published its guide, it called the principles "the bricks" and asked customers to say whether it was building a nice house. A year later, it had run writing training for more than 700 staff and made an introduction to Monzo writing part of onboarding.

Voice drifts for ordinary reasons:

• More writers. Every new freelancer, agency or team member brings their own defaults.
• Pages nobody revisits. The pricing page from two positioning changes ago is still live, still speaking in the old voice.
• Small edits over time. A headline changed for a campaign, a section pasted in from a pitch deck. Each change is fine alone. Together they pull the page apart.
• AI drafts. Language models are very good at producing reasonable copy, and reasonable copy tends to sound like the category rather than the company. A guide made of adjectives gives a model almost nothing to work with, while one made of rules, swaps and examples gives it boundaries. We looked at this in more detail in why all AI copy sounds the same.

Drift rarely shows up as one terrible sentence. It shows up as a site where each page reads fine on its own and the whole thing sounds like several different companies. We saw exactly that when we reviewed 30 pages across 10 SaaS websites, and we cover how to find and fix it in how to keep your brand voice consistent across your website.

Three habits keep a voice intact.

Review against the guide, not against taste. Feedback that cites a principle ("this fails 'name the work': what does the product actually do here?") can be acted on and argued with. Feedback that cites a feeling tends to be ignored, or it triggers a rewrite of the wrong thing.

Audit the live site, not just new drafts. Most voice problems sit on pages nobody is currently working on. Schedule a regular pass over your most visited pages and anything edited since the last review. Our guide to auditing website copy line by line walks through the process.

Update the guide when you learn something. Every time an editor catches the same problem twice, a rule is missing. Every time a rule is overridden for a good reason, an exception is missing. A voice guide that has not changed in two years is probably describing a company that no longer exists.

One last point on consistency: it is not the same as uniformity. Monzo's guide says its writing should feel like it comes from people who share values, not from one person. The aim is for every page to sound like the same company, not for every writer to sound identical.

A brand voice guide checklist

Before you call your guide finished, check that it:

• Defines voice through decisions, with no principle that is only an adjective.
• Gives every principle a passing example, a failing example and an exception.
• Lists your own terms, your swaps and your watch words.
• States how certain you sound and what evidence a claim needs.
• Includes a tone map for your most common situations.
• Shows a few complete pieces, including at least one before-and-after.
• Fits the essentials on one page.
• Names an owner and a date for the next review.
• Separates what was inferred from current copy from what has been confirmed as the intended voice.

The final test is the one from the start. Take a sentence from your own website and give it, with the guide, to two people. If they agree on whether it passes and can point to the rule that decides it, your guide works.

Put your voice guide to work

A guide written this way is precise enough for software to check against, not just people. In Revisi, you add your voice guidance and reference copy to a site, and each page is reviewed against it sentence by sentence, with the reason every line was flagged. If you do not have a guide yet, Revisi can infer a provisional voice from your existing pages and labels it as inferred until you confirm it.

The free scan is a quick way to start. It reads one public page and shows the sentences that are unclear, generic or off-tone, with results in about 30 seconds.

Run a free audit