ScriptFlo vs WriterDuet: Which Screenwriting App Fits How You Write?

Let's concede the big one immediately: if you co-write live, WriterDuet is the best tool for the job. Two writers in the same script at the same time, Google-Docs style, with chat in the margin and every revision tracked forever. That's not a feature bolted onto WriterDuet — it is WriterDuet. Nothing else in the category does it as well, and ScriptFlo doesn't do it at all.

So this comparison isn't really about which app is better. It's about how you write. WriterDuet is organized around the session with a partner. ScriptFlo is organized around the writer working alone — structure templates, planning views, and an AI writing coach, all included in one plan. Pick the app that matches the room you actually write in.

At a Glance

What WriterDuet Gets Right

An honest comparison starts with the other side's strengths, and WriterDuet has real ones.

Real-time collaboration, done properly. This is the headline, and it deserves full credit. Co-writers see each other's cursors, talk in built-in chat, and never lose a line to “wait, which version are you in?” — the revision tracking is effectively infinite. If your writing life is two people and one script, stop reading and go use WriterDuet. We mean that.

The widest export door in the business. FDX, Fountain, Celtx, DOCX, RTF, TXT, HTML, CSV, JSON, and several PDF modes. Whatever pipeline your script is headed into, WriterDuet can probably speak its language. ScriptFlo covers the formats that matter most — PDF, FDX, Fountain, HTML, TXT — but WriterDuet's list is simply longer.

A cheap way in. There's a free browser plan to try, and the paid tiers start at $9.99/month — a third of ScriptFlo's price. If budget is the deciding vote, WriterDuet wins the sticker comparison, and we'll come back to the fine print honestly.

Where the Two Tools Part Ways

Who the app thinks you are

WriterDuet assumes there's a partner in the document. Its best features — live co-writing, chat, revision tracking — light up when someone else is there. Longtime users also note the flip side: an interface that can feel cluttered, with a real learning curve, because it's carrying a lot of collaborative machinery.

ScriptFlo assumes you're alone at 11pm with a scene that isn't working. So it puts the solo writer's tools in reach: 9 story structure templates — Three-Act, Hero's Journey, Save the Cat, Story Circle, Freytag's Pyramid, and more, plus your own custom structure — mapped to planning views for beats, sequences, corkboard, timeline, and canvas. Character and location profiles. Writing goals and a sprint timer. Version history and cloud save. It's a room set up for one person to do deep work.

Coach included vs polish à la carte

WriterDuet's AI offering is ScreenplayProof: an AI proofreading pass priced per script — $20 per proofread, or $30 with reformatting. It polishes what you've written. It is not a writing coach, and it isn't included in the subscription.

ScriptFlo's AI is a coach, not a ghostwriter — and it's part of the plan, not a line item. Fourteen quick actions, Claude-backed: “I'm Stuck,” Improve Dialogue, Character Voice Check, Add Subtext, whole-script analysis, and more. The point is never to generate pages in someone else's voice. It's to ask the questions a sharp reader would ask, as many times as you need, at no extra cost. Prefer to run it on your own terms? Bring your own Anthropic API key — stored encrypted on our servers. Either way, your scripts are never used to train AI models.

The pricing math, honestly

Every WriterDuet subscription is cheaper than ScriptFlo's. Plus is $9.99/month, Pro $11.99, Premium $13.99 — and annual billing shaves those further. If the monthly number is all that matters, WriterDuet wins. Full stop.

But look at how the bundle is assembled. Real-time collaboration and the desktop app arrive at Plus. Custom formatting, reports, revision tracking, and production tools wait until Pro. Page history and restore wait until Premium. AI polish is never included — it's $20 to $30 per script, every script. And user reviews have watched the free tier narrow over the years: project caps, read-only collaborators, the desktop app moved behind the paywall. None of this is scandalous. It's just a ladder, and you should know which rung holds the feature you actually need.

ScriptFlo's answer is one plan. $30/month buys the editor, the 9 structure templates, every planning view, the production breakdown across 18 categories with reports and runtime estimates, and the AI coach with no per-script fees. There's no free tier — just a 14-day trial (card required) — and no tier above you holding anything back.

Moving your work in and out

No lock-in on either side, which is how it should be. WriterDuet exports FDX and Fountain; ScriptFlo imports both (plus plain text) and exports PDF, FDX, Fountain, HTML, and TXT. You can bring an existing script over in minutes, and if ScriptFlo ever stops being right for you, your work leaves in the industry's own formats. Credit where due: if your pipeline needs the longer tail — Celtx, DOCX, CSV, JSON — WriterDuet's export list has no equal.

Choose WriterDuet If…

• You co-write in real time. This is the whole ballgame — nothing matches WriterDuet here, ScriptFlo included.
• You want the lowest subscription price, or a free plan to test the water before paying anything.
• You need exports beyond the standards — Celtx, DOCX, CSV, JSON and more.
• You write on your phone — WriterDuet ships iOS and Android apps.

Choose ScriptFlo If…

• You write alone and want a coach that has read your whole script — included, with no per-script fees.
• You want structure templates and planning views — beats, sequences, corkboard, timeline, canvas — built into the same app as your pages.
• You'd rather pay one flat price than climb a tier ladder and pay $20–30 each time a script needs an AI pass.
• You want production breakdowns, reports, and runtime estimates without upgrading to get them.

Common Questions

Can I move my WriterDuet scripts to ScriptFlo?

Yes. Export FDX or Fountain from WriterDuet — both are on its export list — and import straight into ScriptFlo, which reads FDX, Fountain, and plain text. Formatting comes across; you won't retype a word.

Is WriterDuet's free plan enough?

To start, sure. But the caps arrive fast: 3 projects with one document each, collaborators who can only read, and browser-only access. Longtime users note the free tier has narrowed over the years, so treat it as a test drive, not a home.

What does ScriptFlo's AI cost per script?

Nothing extra. The coach — all 14 quick actions and whole-script analysis — is included in the $30/month plan, on every script you write. Compare that with $20–30 per ScreenplayProof pass and the math shifts quickly for a working writer.

Does ScriptFlo train on my script?

No. Your scripts are never used to train AI models. If you bring your own Anthropic API key, it's stored encrypted on our servers — never in your browser.