How to use AI while maintaining brand voice?

The Challenge: AI Defaults vs. Brand Identity

AI tools like ChatGPT, Claude, and Jasper generate content in a neutral, often corporate tone by default. Without guardrails, your brand voice—the personality that differentiates you from competitors—gets diluted into generic marketing speak. The solution isn't to avoid AI; it's to architect your AI workflows around your specific voice.

Step 1: Document Your Brand Voice

Before touching any AI tool, you need a written brand voice guide. This should include:

• Tone descriptors: Is your brand conversational or authoritative? Playful or serious? Urgent or patient?
• Vocabulary rules: What words do you use? What words are forbidden? (e.g., "utilize" vs. "use")
• Sentence structure: Do you use short, punchy sentences or longer, flowing ones?
• Values and perspective: What does your brand believe? What stance do you take on industry issues?
• Examples: Provide 3-5 real examples of on-brand copy and off-brand copy

This document becomes your AI instruction manual. Without it, you're asking AI to guess.

Step 2: Create a System Prompt

Once you have your voice guide, translate it into a system prompt—the instruction that tells AI how to behave. Here's a template:

"You are a [brand name] copywriter. Our brand voice is [tone descriptors]. We use [vocabulary style]. We believe [core values]. Never use corporate jargon like [forbidden words]. Always sound [specific tone]. Here are examples of on-brand copy: [examples]. Here are examples of off-brand copy: [examples]. When writing, prioritize [priority 1], [priority 2], and [priority 3]."

Save this prompt in a document or use a tool like Notion to version-control it. Update it as your brand evolves.

Step 3: Choose the Right AI Tool for Your Workflow

Different tools have different strengths for voice preservation:

• ChatGPT/Claude: Best for drafting and ideation. Excellent instruction-following with detailed prompts. Free or $20/month.
• Jasper: Purpose-built for marketing with brand voice templates and memory features. $39-125/month.
• Copy.ai: Good for social media and short-form content. $49+/month.
• Runway: Specialized for video scripts while maintaining voice. $15-55/month.
• Internal fine-tuning: If you have 500+ examples of your brand copy, you can fine-tune GPT-3.5 or Claude for higher accuracy ($0.03-0.15 per 1K tokens).

Most CMOs start with ChatGPT + a detailed system prompt. It's the fastest way to test.

Step 4: The Edit-First Workflow

Treat AI as a first-draft tool, not a final-output tool. Your workflow should be:

1. Feed the prompt: Input your system prompt + specific request
2. Generate 2-3 variations: Ask AI to create multiple options
3. Edit ruthlessly: Rewrite 30-50% of the output to match your voice
4. Brand voice checklist: Before publishing, verify tone, vocabulary, and values alignment
5. A/B test: Track which AI-assisted pieces perform best to refine your prompts

This takes 15-20 minutes per piece instead of 45 minutes of writing from scratch—a 60% time savings with better voice consistency.

Step 5: Train Your Team

If multiple people use AI, they need the same voice guide and system prompt. Create:

• A 1-page brand voice cheat sheet for quick reference
• A shared prompt library in Notion or Confluence
• Monthly voice audits where you review AI-assisted content as a team
• A "voice violations" log to catch patterns and adjust prompts

Real-World Example: SaaS Company

A B2B SaaS CMO with a "helpful, not salesy" voice struggled with AI generating corporate copy. She:

1. Documented that her brand uses "you" instead of "organizations," short sentences, and avoids words like "leverage" and "synergy"
2. Created a system prompt that explicitly banned those words and provided 5 on-brand examples
3. Used ChatGPT to draft blog intros, then edited them in 10 minutes
4. Tracked that AI-assisted pieces took 60% less time and scored 8.2/10 on voice consistency (vs. 7.1/10 before)

Within 3 months, her team was producing 40% more content without diluting brand voice.

Common Pitfalls to Avoid

• Vague prompts: "Write in our brand voice" without specifics = generic output
• No editing: Publishing AI output directly = voice erosion
• Inconsistent prompts: Different team members using different instructions = voice fragmentation
• Ignoring feedback: Not updating your system prompt based on what works = stale voice
• Over-relying on one tool: Different tools have different voice strengths; test multiple

Measuring Voice Consistency

Track these metrics to ensure AI isn't diluting your brand:

• Voice audit score: Have 3 team members rate AI-assisted content on a 1-10 voice alignment scale (target: 8+)
• Editing time: Track how much time you spend editing AI output (should decrease as prompts improve)
• Engagement rate: Compare performance of AI-assisted vs. human-written content (should be similar)
• Brand perception: Use quarterly surveys to ask customers if your brand voice feels consistent

Bottom Line

AI doesn't dilute brand voice—unclear instructions do. Document your voice, create a detailed system prompt, use AI for drafting, and edit before publishing. Most CMOs see 60% time savings and maintain or improve voice consistency when they follow this process. The key is treating AI as a co-writer, not a replacement writer.