The AI prompt that writes in your brand’s voice

This brand voice prompt builds a brand voice guide from your business’s own writing, then uses it to write every post, email and page in that voice. You set it up once for each brand.

Use Prompt 1 if you have 3 to 5 pieces of writing to share, and Prompt 2 if the brand is new and has nothing written yet.

Which writing samples to give the AI

Give the AI 3 to 5 pieces of your brand’s best writing.

Here’s what the makers of each AI say about examples:

We recommend you:

• Mix the formats, like a blog post, an email and a social post, so it learns the voice and not one topic.
• Pick the same kind of writing you want it to produce.
• Use the pieces you’re proudest of.
• Include typical pieces too, not only your punchiest. The AI copies whatever shows up most.
• Leave out anything AI wrote or someone else rewrote.
• Add 2 or 3 things the brand never does.

In my experience, 2 or 3 “don’t” rules help a lot, on top of plenty of examples of what to do. After a few tries, I see what the AI keeps doing and tell it to stop, like the tell-tale signs that AI wrote it.

Prompt 1: the brand voice prompt for brands with writing

Use this prompt when your brand already has writing you like. It asks about the brand and its audience first, then asks for your samples one at a time.

You are helping me build a brand voice guide for one brand. Interview me first. Ask one question at a time and wait for my answer before you ask the next.

1. What is the brand called, and what does it sell?
2. Who buys from the brand, and what do they care about most?
3. What will you write for this brand? For example web pages, emails, social posts or blog posts.
4. Ask me to paste a writing sample. After each one, ask for the next. Stop when I have shared 5, or when I say done.

When you have everything, write the brand voice guide. Cover:

- Audience: who the brand writes for, from my answers.
- Tone: how the writing feels to that audience.
- Rhythm: sentence length, paragraph length and how pieces open.
- Word habits: words and phrases the brand uses again and again.
- Say this instead: words or habits the brand avoids, each paired with what it says instead.

Rules for the guide:

- Only include patterns that show up in at least 2 samples.
- Describe the mix, not the extremes. If sentence and paragraph length vary, say how and when.
- Back each point with a short quote from my samples.
- Quote word for word. Never reword a quote.
- Keep the voice rules as specific as the guide. If the guide says sentence length varies, the rule says so too.
- If the samples don't show enough for a point, say so. Don't guess.
- Learn how the brand writes, not what it writes about.
- Write most rules as something to do. Add 2 or 3 "never" rules for the habits that would sound least like the brand.

End the guide with 5 to 8 voice rules I can save and reuse.

Then follow those rules for everything you write in this chat. Write 2 sentences about the brand in its voice so I can check it, then ask me what to write first.

Prompt 2: the brand voice prompt for a brand with no writing yet

Use this prompt when the brand is new and has no writing yet. It interviews you one question at a time, and your answers become the samples.

You are helping me build a brand voice guide for a new brand that has no writing yet. Interview me. Ask one question at a time and wait for my answer before you ask the next. Tell me to answer the way I'd say it out loud, not the way I'd write a report.

1. What is the brand called, and what does it sell?
2. Who buys from the brand, and what do they care about most?
3. What will you write for this brand? For example web pages, emails, social posts or blog posts.
4. How would you explain what the brand sells to a customer in 2 or 3 sentences?
5. A customer writes in upset because something went wrong. Write the first 2 sentences of the brand's reply.
6. What words or phrases should the brand never use? For each one, what does it say instead?
7. What phrases do you catch yourself saying when you talk about the business?
8. Name a brand whose writing you like and one you don't. What makes the difference?

When you have everything, write the brand voice guide. Cover:

- Audience: who the brand writes for, from my answers.
- Tone: how the writing should feel to that audience.
- Rhythm: sentence length, paragraph length and how pieces open.
- Word habits: words and phrases the brand should use.
- Say this instead: words or habits the brand avoids, each paired with what it says instead.

Rules for the guide:

- Base every point on my answers, not on what brands usually sound like.
- Back each point with a short quote from my answers. Only quote what I typed. Never quote your own questions.
- Quote word for word. Never reword a quote.
- Keep the voice rules as specific as the guide. If the guide says sentence length varies, the rule says so too.
- If a point would fit any brand, like "short sentences" or "be concise," leave it out unless my answers show it.
- Describe the mix, not the extremes. If sentence and paragraph length vary, say how and when.
- If my answers don't show enough for a point, ask me one follow-up question instead of guessing.
- Write most rules as something to do. Add 2 or 3 "never" rules for the habits that would sound least like the brand.

End the guide with 5 to 8 voice rules I can save and reuse.

Then follow those rules for everything you write in this chat. Write 2 sentences about the brand in its voice so I can check it, then ask me what to write first.

Where to save your brand voice guide

Save your brand voice guide inside a space for that one brand, so every chat there starts in the brand’s voice. Paste the 5 to 8 voice rules, or the whole guide, into the instructions of one of these:

• ChatGPT: a Project or a custom GPT
• Claude: a Project
• Gemini: a Gem

Make one for each brand you write for. Custom instructions apply to every chat you have, so a brand voice saved there leaks into everything else.

If the writing starts to drift, paste the guide back in, or ask the AI to check your draft against the guide and fix what doesn’t match.

Want to learn from someone else’s writing instead? The writing style prompt breaks down any piece you admire. For a blunt read on a draft before it goes out, use the honest feedback prompt.