How to Build Your AI Brand Voice (That Actually Sounds Like You)

Ever asked ChatGPT to draft a blog or email and thought, “Yeah… that doesn’t sound like us at all”? This is a pretty common reaction when first testing out the AI for business waters.

As AI-generated content becomes the norm, brand voice inconsistency has become one of the biggest content headaches out there.

Businesses are producing more content than ever with tools like ChatGPT, Jasper, and HubSpot’s Breeze Copilot—but so much of it ends up sounding vague, robotic, or just plain off. And that’s a problem. Because when your content doesn’t sound like you, it doesn’t connect.

Your brand voice is your company’s personality in words. It’s how people recognize and remember you. And in a sea of AI-written sameness, personality is your competitive edge—it’s what captures attention, builds trust, and keeps your message from disappearing into the crowd.

Over the past decade, I’ve helped businesses across industries develop and document their brand voices. I’ve led dozens of brand personality workshops—and I’ll admit, when AI tools first rolled out, I wasn’t impressed.

The output felt generic, many phrases were used over and over, and it lacked the nuance that makes content feel...human.

But as the tools evolved—and I learned how to feed them the right inputs, examples, and voice instructions—my opinion on generative AI has done a complete 180.

Today is the worst AI will ever be. It’s only getting better. And when you teach it to sound like you, the results are faster, smarter, and surprisingly spot-on.

In this guide, we’ll break down:

• How to define your AI brand voice (starting with a few key adjectives)
• How to analyze your tone using tools like ChatGPT and Jasper
• How to apply Nielsen Norman Group’s four tone dimensions
• How to tap into your team for rich voice insights

And how to put it all together into a custom GPT or AI assistant that scales your content without losing your personality.

Let's get to it.

why your brand voice matters more than ever (thanks to AI)

Brand voice has always mattered, but in the age of AI content, it’s mission-critical. Why? AI makes it easy to pump out content – blogs, emails, social posts – at an unprecedented scale. Without a strong voice, all that content risks becoming noise.

Imagine dozens of companies in your industry all using similar AI tools to write their posts; how will you stand out? A distinctive voice is what will set your content apart from the rest of the robo-content pack.

A consistent, authentic voice isn’t just a “nice-to-have” – it directly impacts how audiences perceive and trust you.

Research shows that a unique brand voice enhances competitive advantage and resonance with customers. It’s the secret sauce that makes a reader recognize your blog post or email without even seeing the logo.

On the flip side, losing your voice means losing your impact. Companies that settle for one-size-fits-all, bland AI content are already lagging behind. They’re not just producing bland content – they’re failing to engage, resonate, and build trust with their audience.

On the flip side, AI content that does reflect your brand voice creates memorable, trustworthy experiences for your readers.

Simply put, brand voice is your brand’s personality. In a world where AI can generate what you say, your voice is how you say it – and that “how” is what makes a lasting impression.

step 1: define your brand voice using simple descriptors

Before you even touch an AI tool, you need to define your brand voice clearly. Think of this as laying the foundation – you can’t scale what you haven’t defined. The good news is defining your voice can be a fun, creative exercise.

Start with a few key adjectives or phrases that capture your desired tone. Are you playful and witty, or professional and empathetic? Bold and authoritative, or casual and friendly?

Gather your marketing team (and anyone who writes or speaks for the company) and brainstorm: if our brand were a person, how would we describe them?

A simple way to approach it is to literally ask: “If a movie were made about our brand, who would play the lead? How would they communicate?”

Jot down the first descriptors that come to mind, along with examples. For instance, your brand might be knowledgeable, honest, and a little quirky—like Bill Nye—or warm, trustworthy, and funny, similar to Leslie Knope from Parks and Rec.

Aim for 3–5 core traits. These will become your north star for your voice.

It’s equally important to clarify what you are not. For each trait, think of a flip side to avoid. For example, “we’re witty but never snarky,” “professional but not stuffy,” “casual but not careless.” These do’s and don’ts further sharpens your voice guidelines.

Next, take those descriptors and map them onto a framework. One of my favorite frameworks comes from the Nielsen Norman Group, which identifies four dimensions of tone of voice:

• Funny vs. Serious: Do you inject humor, or keep a straight-laced tone?
• Formal vs. Casual: Are you polished and formal, or conversational and informal?
• Respectful vs. Irreverent: Do you maintain a respectful, polite tone, or are you edgy and irreverent?
• Enthusiastic vs. Matter-of-fact: Is your tone passionate and excited, or calm and neutral?

Consider where your brand falls on each of these spectra. You don’t have to choose extremes – maybe you’re mostly casual but just a bit formal in certain contexts, or generally enthusiastic but not overly cheerleader-ish.

The point is to paint a clearer picture of your tone.

For example, you might decide: “We’re 80% casual and 20% formal; we lean respectful over irreverent; we’re more enthusiastic than matter-of-fact, and we use humor sparingly – a bit witty but not outright jokey.”

This exercise forces you to articulate your voice in a nuanced way. (If you have existing content, you can also evaluate it along these lines to see if reality matches your goals – more on that in a moment.)

By the end of Step 1, you should have a short list of voice characteristics and a rough profile of your tone on those four dimensions. Congratulations – you’ve defined your brand voice without any AI. You now have the rulebook that your AI content should follow.

step 2: run an AI voice audit on your content (yes, really)

Now that you’ve defined how you want to sound, it’s time to see how you actually sound – and this is where AI can be a huge help. One advanced (but surprisingly easy) tactic is to use generative AI to analyze your existing content and extract tone characteristics.

Essentially, you’re going to point AI inward, at your own materials, before pointing it outward to create new stuff.

Start by gathering a few pieces of content that you feel best represent your brand (or, if inconsistency is the issue, grab a mix of examples). These could be blog articles, website copy, marketing emails, even social media posts.

Feed them into a tool like ChatGPT or Jasper and ask for an analysis.

For example, you might prompt: “Analyze the tone and style of the following content. What adjectives would you use to describe the brand’s voice? What patterns do you notice?”

The AI might come back with something like: “The voice is upbeat and educational, using simple, approachable language with a friendly tone.”

Or perhaps, “Your content comes across as professional and authoritative, with frequent optimistic phrases and a dash of wit.”

This exercise can be eye-opening. You’ll quickly see if the way you think you sound (from Step 1) matches how your content actually comes across. If the AI describes your tone in ways that align with your defined voice, great – you have a solid baseline.

If not, it’s a clue that your team’s writing might be veering off-course, and you now know which qualities to dial up or down.

You can take this a step further by asking AI to compare different pieces.

For instance: “Here are two blog excerpts – one from last year, one from last week.  Do they sound like they came from the same brand? If not, what’s different?”

This can surface subtle drifts in tone that happen over time or between writers. Jasper, which is geared toward marketing content, can similarly analyze tone or even help build a tone profile if you feed it enough input.

Another pro tip: use AI to suggest refinements to your voice. Let’s say your initial voice definition felt a bit generic (e.g., “friendly and professional” – which describes just about everyone).

You could prompt ChatGPT with something like, “Our current brand voice is [X and Y]. How could we make it more unique? Give us a few new tone elements or descriptive quirks that fit our industry.”

You might get suggestions such as adding more playfulness, or adopting a storytelling vibe, or using more inclusive “we’re in this together” language. Consider some of these ideas as you fine-tune your voice.

Another really important consideration is to be mindful of data privacy and confidentiality during this step. If you’re feeding proprietary content into a public AI tool, make sure it doesn’t contain sensitive information or anything covered by privacy regulations. Nearly 75% of tech professionals rank data privacy among their top concerns with AI, and 40% call it their number one worry– so you’re wise to be cautious.)

If in doubt, remove or mask client details, or use privacy features (OpenAI, for instance, allows turning off chat history to not use inputs for training). 

step 3: refine your voice with the Nielsen Norman tone dimensions 

Let’s revisit those four tone-of-voice dimensions from Nielsen Norman Group so we can put them to work:

• Funny vs. Serious
• Formal vs. Casual
• Respectful vs. Irreverent
• Enthusiastic vs. Matter-of-fact

This is a great technique for advanced refinement of your brand voice.

First, use these dimensions as a lens to evaluate and tweak your content. You can ask an AI assistant to rate or adjust a piece of content on a specific dimension.

For example, you can use the following prompts: 

• Rewrite the following paragraph to be slightly more casual and enthusiastic, while remaining respectful.
• On a scale of 1-10, how formal does this email sound, and can you make it 2 points less formal?

The AI will interpret that and adjust wording (maybe contracting “do not” to “don’t,” adding a warm exclamation here or there, etc.). This helps you modulate tone systematically.

Consider creating a simple tone chart for your brand using these dimensions – essentially a quick reference of where you sit on each. You might decide your tone is, say, 2/5 Funny (mostly serious with occasional light humor), 1/5 Formal (very casual), 5/5 Respectful (always polite, never snarky), and 4/5 Enthusiastic (upbeat and positive).

Now, you can literally feed those parameters into a prompt when generating content: “Write a social post about our new product in our brand voice – tone should be 0% formal (completely casual), very respectful, high enthusiasm, with a hint of humor.”

It might feel odd to quantify voice, but I’ve found that AI often responds well to explicit instructions like this. You’re basically giving the model a mini style guide each time.

Step 4: build a stronger voice with team feedback and creative prompts

Defining your brand voice isn’t just a top-down decision—it should come from the people who live and breathe your brand every day. Some of the best insights come from your team (and even your customers).

At media junction, we like to treat this as a creative deep dive. During our brand personality workshops, we ask quirky but revealing questions like:

• If our brand were a famous person or fictional character, who would play the lead?
• What five adjectives best describe our personality?
• How do we want customers to describe us to their friends?
• What’s our brand’s spirit animal—and why?
• If our brand were a vehicle, what would it be?
• Who isn’t our brand? (Sometimes defining the opposite is just as helpful.)

These kinds of questions lead to some surprising clarity. I once had a cybersecurity client say their brand would be played by The Rock—tough, reliable, but approachable. That told me more about their tone than any style guide ever could.

You don’t need a big workshop to do this. Even a short internal survey or roundtable can surface patterns and create buy-in.

When your sales reps, marketers, and leadership team align on how the brand “sounds,” it’s easier to keep that voice consistent across channels.

So where does AI come in? Two key places.

First, these voice insights become part of your prompts. If your team sees your brand as a “friendly teacher with a dry sense of humor,” you can tell ChatGPT or Jasper to write in the tone of a friendly, knowledgeable teacher with a hint of wit.

If your brand’s spirit animal is a border collie—focused, energetic, and loyal—you can prompt AI to channel that energy in your social captions. It might sound quirky, but it works. You’re giving the AI a vivid character to mimic, and the output tends to hit closer to home.

Second, this process gives you stronger inputs to train your AI tools. Jasper allows you to set tone preferences. HubSpot’s new Breeze Copilot taps into your CRM and blog content to get a feel for your brand automatically—but don’t rely on automation alone.

The more intentional you are about feeding it real examples and voice guidelines, the more it can mirror your tone accurately.

Think of AI as a new team member. You wouldn’t hand a junior writer the keys without onboarding. The same goes for AI. Off-the-shelf models don’t know your voice yet—they need training, context, and correction. (We break this down in our AI Business Myths article—spoiler: AI isn’t plug-and-play.)

Bottom line: Your brand voice gets stronger when everyone contributes to defining it—and AI gets better when you teach it to sound like you.

step 5: scale your content, keep your voice

Once you’ve defined your voice, it’s time to put it to work—at scale. Tools like ChatGPT, Jasper, and HubSpot’s Breeze Copilot can help you crank out blogs, emails, and social posts at lightning speed. But here’s the deal: efficiency means nothing if your content doesn’t sound like you.

The key? Build a custom AI assistant that already knows your voice.

create a custom voice GPT 

ChatGPT, Jasper, and HubSpot all now allow you to train a custom AI on your brand voice—so you don’t have to repeat yourself in every prompt. Instead of constantly saying, “Use a confident, conversational tone with a hint of humor,” you can bake those instructions directly into a custom GPT.

In ChatGPT, this means building your own custom GPT assistant with pre-set voice instructions. You can even upload documents—your brand voice guide, personality surveys, sample blog posts, tone dimensions, approved phrasing, you name it.

The GPT uses this reference material to guide its output, which means you get consistent, on-brand content every time.

Jasper’s Brand Voice feature does something similar, letting you upload content samples and brand guidelines to lock in your tone. HubSpot’s Breeze Copilot is designed to pull voice cues from your CRM, emails, and blog content—but it gets even better when you give it clear, structured input.

The bottom line is: you don’t have to prompt from scratch every time. Build the voice once, and your AI will remember it—so you can scale your content with confidence.

still, be clear in prompts (especially early on)

Even with a trained model, you’ll sometimes need to steer the output. So don’t be afraid to get specific:

“Write a 500-word blog intro in our brand voice—confident, conversational, with short, punchy sentences. Sound like a trusted coach.”

Include tone tweaks as needed:

• “Make it slightly more casual”
• “Dial up the enthusiasm by 10%”
• “Cut the jargon but keep it authoritative”

match the medium and the persona

Your brand voice should stay consistent—but tone? That’s where you flex.

Tone shifts based not just on where your content lives (blog, email, social), but also who you’re speaking to. The way you talk to a CFO shouldn’t be the same as how you talk to a marketing coordinator or an IT manager.

Different audiences expect different energy, detail, and delivery.

Take format first. A blog post might take on a narrative, educational tone to pull readers in and provide depth. An email, on the other hand, should feel more direct and personal—like a one-to-one conversation. LinkedIn leans professional but still human, while Twitter (or X) is your chance to be punchy, witty, and scroll-stopping.

Now layer in persona-based nuance.

When you’re talking to executives, you may want to lead with business outcomes and speak in a slightly more formal, strategic tone. If you're writing for marketers, you can be bolder and more creative—focusing on big-picture ideas, trends, and inspiration. A technical buyer? They’ll want precision and clarity, with just the right amount of jargon to show you know your stuff. And for everyday end users, keep it helpful, friendly, and focused on benefits, not buzzwords.

AI can help you navigate all of this—if you guide it with the right context. Instead of a one-size-fits-all prompt, tailor your asks:

• “Write a blog introduction about [topic] in our brand voice. It should speak to CMOs, so keep it confident, strategic, and slightly provocative—something that sparks big-picture thinking.”

Or:

• “Draft a feature announcement email for IT managers. Use a professional tone, be clear and to the point, and avoid marketing fluff.”

These micro-adjustments help your AI outputs feel intentional and aligned, even as you adapt across formats and audiences.

lock it in: build a GPT that knows your voice

You’ve already done the hard work—defining your voice, surveying your team, analyzing tone. Now it’s time to codify that voice into a custom GPT assistant.

With ChatGPT, Jasper, or HubSpot’s Breeze Copilot, you can build a tailored assistant that knows your voice, understands your audiences, and references your uploaded resources—everything from brand guides to content examples to persona docs.

With the right setup, AI becomes your most consistent content creator—able to flex tone without losing your voice.

You’re not just using AI. You’re training it to speak like you.

That’s how you scale content without sounding like a robot. And honestly? Who wouldn’t want that?

what’s next: turn your brand voice into action

By now, you’ve done more than just learn how to define a brand voice—you’ve learned how to translate it into AI tools that can scale your message without losing your identity.

You understand why voice matters more than ever in the age of AI. You know how to define it, refine it, and teach it to AI. You’ve got a framework to ensure your content doesn’t just sound good—it sounds like you.

So what’s next?

If you’re ready to put this into practice, join us for the AI Content Bootcamp—a hands-on workshop where we help you build your AI-powered content engine. You’ll walk away with:

• A clearly defined brand voice tailored for AI use
• A custom GPT or AI assistant trained to sound like your business
• Prompt templates for blogs, emails, and social that actually convert
• Confidence that your content will sound consistent—no matter who (or what) is writing it
• We’ll guide you step-by-step through building a brand voice that’s scalable, sustainable, and unmistakably yours.

Because the brands that win with AI? They’re the ones that sound human.

👉 Join the AI Content Bootcamp

Let’s build something brilliant together.