AI developmental editor for book authors

You finished the draft. Now find out what it needs.

Penmark Studio is the editing studio for novelists, memoirists and narrative nonfiction authors with a manuscript in hand. Six editorial reviews — developmental, line, continuity, voice, chapter and reader experience — returned in under two minutes, with ranked action items you can actually work through.

A freelance developmental edit on an 80,000-word manuscript runs $1,500–$3,000 for one pass and takes two to six weeks. Penmark starts at $15/month and you can run the pass again tonight.

Start your 14-day free trial
  • No credit card required
  • Your prose is never rewritten
  • First review back in about a minute

Not for everyone: Penmark does not draft, ghostwrite or co-write. If you want AI to produce prose, this is the wrong tool. It is built for authors who have already done the writing and need to know what to fix.

the_quiet_house.studio

Chapter 3 · 2,140 words

What Marta Knew

The morning after the storm, Marta found the back door standing open and the kitchen floor pale with snow. She did not call out. She had stopped calling out years ago.

Whatever it was had taken the bread and left the knife. Whatever it was had sat at her table.

She put the kettle on and watched her own hands. They were not shaking, which surprised her…

Writing a book is lonely. Editing one is expensive.

Beta readers give you vibes, not direction.

Developmental editors cost thousands and take weeks.

You lose the thread across chapters and drafts.

Six reviews. One editor who knows your book.

Chapter Review

Pacing, voice, and line quality on a single chapter. Recommendations ranked by impact.

Continuity Check

Character, setting, and timeline consistency across any chapters you select. Every inconsistency flagged with a fix.

Voice Stability

Where your voice wanders between chapters and what to adjust.

Developmental Edit

Full-manuscript review against bestseller standards in your genre.

Line Edit

Word-level precision, cut-the-fat candidates, and rhythm notes on a single chapter.

Reader Experience

Claude reads as your target audience and reports where attention drops and where it spikes.

Your manuscript, tracked like a manuscript.

Version history on every chapter.

Every save preserved, every revision traceable.

Chapter 3 v1

Mon · 9:14 AM

Action items become a checklist.

Feedback from every review becomes work you can mark resolved as you revise.

  • Tighten Chapter 3 opening
  • Resolve timeline gap in Chapter 5
  • Sharpen dialogue on page 47
  • Revisit Chapter 7 closing

A revision dashboard for the whole book.

Open feedback, weekly progress, and chapters that still need work — all in one view.

Open items

12

Resolved this week

5

Chapters needing work

3

Act 178%
Act 252%
Act 334%

Reading mode hides the interface.

Export to .docx, .md, or .pdf when you're ready to send.

Chapter 3

The morning after the storm, Marta found the back door standing open and the kitchen floor pale with snow. She did not call out. She had stopped calling out years ago.

Whatever it was had taken the bread and left the knife. Whatever it was had sat at her table.

Feedback from a senior editor, on demand.

Claude reviews your work with the standards of editors at Knopf, FSG, Riverhead, and Scribner. It knows your voice, your audience, and the books you want yours to sit beside. It quotes passages. It ranks recommendations. It never pads with generic praise.

Chapter 3 opens on the wrong beat. You've buried the inciting moment under two pages of weather. Cut to line 47 and the chapter sharpens. The closing image earns its weight.
Sample chapter review excerpt

The three things authors ask before they trust an AI with a book.

Will it flatten my voice?

It never writes a word of your manuscript. Penmark returns notes, quoted passages and ranked action items — you decide what to change. The Voice Stability review exists to catch drift in the voice you already have, not to replace it.

Who can see my manuscript?

Only you. Your work is scoped to your account, we do not train models on it, and we do not sell or share it. Export everything as a ZIP or delete your account and its contents whenever you want.

Does this replace my editor?

No. It replaces the three or four expensive passes you would have burned on problems you could have found yourself. Your human editor gets a stronger manuscript and bills you for less.

Built with the first authors through the door.

Penmark Studio is early. We are opening to a small group of authors first and building the studio around what their manuscripts actually need. We would rather say that plainly than invent a wall of five-star quotes.

Early access. Join the first 200 founding members.

Built for authors writing

Literary fictionMemoirNarrative nonfictionCommercial fiction

Weighing the alternatives? Penmark vs AutoCrit · Penmark vs ProWritingAid

Pricing

Pricing that respects the work.

Plans from $15/month. No credits, no per-review charges. Founding members lock in $19/month for life.

Questions.

Your next draft deserves a real editor.

Start your manuscript