Can you train AI to match your brand voice?

In case we haven't worked this out yet, AI tools like ChatGPT are not mind readers. Sadly. And as much as I love using AI tools in my business, I think there’s a dangerous myth floating around that you can just plug in a few prompts and out pops the perfect brand voice.

If only it were that easy.

The truth is, training AI to sound like you takes time. It takes feedback. And it takes a whole lot of trial and error. But if you’re willing to put in the effort, the result can be seriously powerful.

So let’s break down how to actually get ChatGPT to sound like your brand — and how to avoid ending up with yet another slightly-too-polite, overly-robotic AI voice.

Why your brand voice matters in the AI age

Here’s the thing. AI is everywhere now. And in a sea of AI-generated content, your brand voice is one of the only things that can still set you apart.

But the more we rely on tools like ChatGPT, the easier it is to forget what makes our brand feel human. I’ve seen so many businesses start sounding exactly the same since using AI. You know the vibe: polished, professional, slightly robotic. Too perfect. And kind of... boring. It's a whole separate conversation as to how people are now calling the em dash (—) the 'ChatGPT dash'. But that does prove how people are becoming accustomed to the type of text that's generated using AI.

Which is why the goal shouldn’t necessarily be to get AI to write for you. It should be to get it to write with you. And that’s where training comes in.

How I train AI to match my brand voice

I use ChatGPT every day for brainstorming, reviewing content, summarising reports, generating ideas, and even proofreading. But I don’t let it speak as me until I’ve done the legwork.

Here’s what that legwork looks like:

1. Create a brand voice guide

Before you can teach AI your voice, you need to define it yourself. Think of this like your tone of voice cheat sheet.

Include:

• Personality traits (e.g. casual, curious, a little cheeky)

• Words you do and don’t use

• Common phrases or expressions

• Sentence style (short and punchy? Long and lyrical?)

Once you have this, you can give it to ChatGPT in the form of a prompt:

Prompt example: "You are a website strategist and designer with a tone that is casual, insightful, a bit cheeky but always professional. You avoid jargon and write like you're talking to a smart friend over coffee. No exclamation points. No robotic phrases. Use contractions and rhetorical questions where relevant. Here's an example of my tone: [insert paragraph you’ve written yourself]. Please use this voice going forward."

Then I literally copy-paste that prompt into every new chat I start with AI. Every. Time. (If you're using the same chat or same project then you won't need to keep repeating yourself).

2. I give examples of what I like and don't like

AI learns best through comparison. So I’ll often give it a paragraph I wrote and ask it to match the tone. If the output’s off, I’ll say exactly what didn’t work:

• "This sounds too formal. Try again but be more conversational."

• "Can you make this shorter and more playful?"

• "Use more specific examples and remove the fluff."

Over time, ChatGPT does start to learn your preferences (when it's in the same conversation). It’s not perfect, but the more feedback you give, the better the results.

3. I use training prompts

I can't always explain exactly how I write and so how I want AI to write. So I make it analyse my work for me to tell itself what it needs to do. This means using prompts like:

Prompt: "Analyse this paragraph and list the tone of voice elements that define it. Then recreate this tone in a new paragraph about [topic]."

Or: "Here are 3 blog posts I've written. Identify the consistent tone and suggest 5 writing guidelines based on it, that you can use to write this style of blog post going forward."

These kinds of meta prompts help AI build a framework to follow in future responses.

4. I don't let AI replace the final edit

Even when AI nails the voice, I always do a final pass. I trim bits. Reorder paragraphs. Add a joke or a story to make it more personal to my experience.

It’s still my brain doing the magic. AI is just giving me a starting point. Like a very enthusiastic intern who means well but still needs supervision.

Can you actually trust AI with brand voice?

Honestly? Not at first. Like you couldn't with a brand new colleague. But with time, feedback, and a bit of systemising, you can trust it to sound more like you. The trick is never assuming it gets it right the first time.

And if your brand voice is a big part of your business (like it is for mine), it’s worth putting in the effort to make sure AI isn’t diluting it.

Because your voice is your edge. It’s the thing that makes someone stay on your page longer. The reason someone DMs you instead of someone else. You don’t want to lose that just because it’s faster to let AI do the writing.

Ready to train AI to match your brand voice?

If you want to use AI in your content strategy, I’m all for it. But if you want your content to sound like you and not every other person using the same tool, then put the work in to train it.

Start with a tone guide. Show it examples. Give feedback. And remember that just like a new team member, it takes time for AI to really get it.

Need help defining your brand voice, making sure your content doesn’t sound like a copy of a copy, or training AI to match your brand voice? That’s what I do. Let’s chat about how to build a voice-first website that still sounds like you – even if you’re using AI behind the scenes. You can contact me here.