Custom AI writing models

AI that writes
like you

A model trained on your actual writing — not a tone selector, not a style prompt — so every piece of content carries your voice. At any scale.

Brand voice tools don't train. They pretend.

Every AI writing tool claims to learn your voice. They analyze a few samples, build a prompt, and hope for the best. The result drifts after two paragraphs and reads like everything else on the internet.

  • Prompt engineering fades

    System prompts lose influence as context grows. By paragraph three, your "brand voice" is gone.

  • One model fits nobody

    Jasper, Copy.ai, and Writer use the same base model for every client. Your voice is a costume, not a characteristic.

  • Detection is the new gatekeep

    AI detectors flag generic patterns. Post-hoc "humanizers" introduce errors. Neither solves the root problem.

  • Writers don't scale

    Freelancers cost $8–15K/month per voice. Onboarding takes weeks. They leave, and the voice leaves with them.

Your writing becomes the model

We don't prompt-engineer your voice. We fine-tune a dedicated language model on your actual writing — vocabulary, rhythm, structure, instinct — so the output isn't an imitation. It's an extension.

1

Upload your writing

Upload 50+ writing samples — blog posts, newsletters, articles, emails. Anything that sounds like you. The system validates quality and flags gaps automatically before training begins.

Fully automated. No human ever reads your writing.
2

Your model trains

A dedicated model is fine-tuned on your writing. Not approximated through prompting — the model's parameters change to learn your patterns directly from your prose.

Private infrastructure. No third-party clouds or APIs.
3

Validation & scoring

Every model is tested against AI detectors, scored for voice consistency, and validated against your original corpus before delivery.

4

Write at scale

Submit briefs through your dashboard. Receive content in your voice within minutes, not days. Every piece you edit makes the model sharper — it learns what you keep and what you change.

The difference between a voice prompt and a trained model is the difference between an impression and a fingerprint.

Trained models,
not engineered prompts

Every other tool wraps the same model in a different instruction set. Ghostweight changes the model itself.

Prompt-engineered tools
Voice defined by text instructions
Tone drifts after 2–3 paragraphs
Same base model, every client
AI-detectable patterns by default
No learning from your corrections
Your data routed through third-party APIs
Ghostweight
Voice built into the model itself
No drift — your voice is the model
Dedicated model per client
Passes AI detectors by default
Every edit improves the next generation
Your data stays on private infrastructure

For people who write
for a living — or should

Ghostweight is for anyone whose reputation rides on how they write — whether that's a team producing content for clients, or a founder whose voice is the brand.

Content agencies

Currently spending $8–15K/mo on writers

Managing 5–20 client voices with rotating freelancers. Every new writer means weeks of onboarding. Every departure means starting over. Ghostweight is a voice that never leaves.

Founders & executives

Currently spending $2–10K/mo on ghostwriters

You know you should be on LinkedIn, writing newsletters, publishing thought leadership. You don't have the hours. A model trained on your actual writing produces drafts that sound like you sat down and wrote them.

Brand content teams

Currently spending $5–15K/mo on freelance

Three writers, five markets, one voice that keeps fracturing at scale. The trained model becomes the style guide — new contributors write on-brand from day one, without a six-week ramp.

Train once. Write forever.

A one-time training fee to build your voice model, then a monthly plan based on how much you write.

Voice training
$3,500
One-time per voice. Covers corpus intake, model training, validation, and deployment to your account.
Starter
$799/mo
20 pieces per month
1 trained voice
Dashboard access
Agency
$2,999/mo
Unlimited pieces
Up to 5 voices
Dedicated support

Get a free voice analysis

See your writing fingerprint

Upload a few writing samples and we'll map your voice — sentence rhythm, vocabulary patterns, structural habits, and tonal range. No model training, no commitment.

1

Upload 5–10 samples

2

Automated voice analysis

3

Your writing fingerprint

Get your free analysis

Free. No commitment. Your writing stays private.

Before you ask

How is this different from Jasper's Brand Voice?

Jasper analyzes your samples and builds a text instruction. The same base model serves every client. Ghostweight trains a dedicated model — a permanent change to the AI's internal parameters — on your writing. Jasper's voice fades as the text grows. A trained model doesn't drift, because your voice isn't an instruction. It's the model.

How much writing do I need to submit?

A minimum of 50 samples, roughly 50,000+ words. Blog posts, newsletters, articles, emails — anything that represents how you want to sound. More data produces sharper results. Our system validates your corpus automatically and flags any gaps before training begins.

Will the output pass AI detectors?

Yes. Every generation runs through our anti-pattern scoring system, which flags and regenerates any text with detectable AI patterns. Because the model is trained on human writing — yours — the output is structurally different from generic AI text.

How does the model improve over time?

Every edit you make to generated content becomes a training signal. We compare your corrections against the original output and periodically retrain the model on those preferences. It learns what you keep and what you change — so every quarter, the model gets closer to how you'd write it yourself.

Is my writing data safe?

Your corpus is processed and stored exclusively on our private infrastructure. It is never sent to third-party AI providers, cloud APIs, or shared with other clients. Your trained model serves only your account. If you cancel, all data and the model are permanently deleted.

What does a "piece" include?

A piece is any content unit up to 2,500 words — a blog post, a newsletter, a LinkedIn article, a white paper section. Short-form content like social posts or email subject lines counts as a fraction of a piece.

Who owns the trained model?

Your writing corpus remains yours. The trained model runs exclusively on our infrastructure and serves only your account. We don't use your data to improve other clients' models or any general-purpose system.

Can I use emails as training material?

Yes — professional emails, client communications, and internal memos can be excellent training data because they capture your unfiltered voice. We process all materials through automated pipelines. No human reads your content. Sensitive information is stripped automatically before training.

Your voice deserves
more than a prompt

Start with a free voice analysis. Submit a handful of writing samples and we'll show you exactly how a trained model captures what makes your prose yours.

Get started