TL;DR: Grammarly is the everyday editor: it checks grammar, tone and clarity everywhere you type, with a usable free plan and Pro at $12/month billed annually. ProWritingAid is the deep editor: 25+ manuscript-wide reports on pacing, repetition and style, Premium at $10/month billed annually, plus a $399 lifetime option Grammarly does not offer. Pick Grammarly for email, work and web writing; pick ProWritingAid if you write books, theses or long-form work – especially in Scrivener.
Grammarly vs ProWritingAid at a glance
| Feature | Grammarly | ProWritingAid |
|---|---|---|
| Free plan | Basic grammar and spelling, tone detection, 100 AI prompts/month | Checks 500 words at a time with limited daily reports and rephrases |
| Paid price | Pro $30/month monthly, or $12/month billed annually ($144/year) | Premium $30/month monthly, or $10/month billed annually ($120/year); Premium Pro $12/month annually |
| Lifetime option | None – subscription only | Premium $399 one-time; Premium Pro $699 one-time |
| Where it works | Browser, desktop, mobile, Google Docs, Word and most apps as you type | Web editor, desktop, Word, Google Docs and Scrivener integration |
| Depth of feedback | Fast, in-line corrections for grammar, clarity and tone | 25+ document-wide reports: pacing, echoes, sticky sentences, dialogue and readability |
| Plagiarism | Included in Pro | Costs extra on standard tiers |
| Best for | Professionals, students and anyone writing short-form daily | Novelists, academics and long-form writers self-editing |
Prices checked October 2026 against both official pricing pages.
What does Grammarly do best?
Grammarly’s advantage is presence. It sits inside your browser, email, documents and phone keyboard, quietly fixing grammar, punctuation and tone in the moment, which is why its free plan is enough for many casual writers. Pro raises the AI prompt allowance to 2,000 a month, adds full-sentence rewrites and tone adjustments, and includes plagiarism detection. If most of your writing is under a few thousand words and spread across a dozen apps, nothing here is seriously competing with that convenience.
What does ProWritingAid do best?
ProWritingAid analyses the whole document, not just the sentence your cursor is in. Its reports surface the problems authors actually revise for: pacing that sags, overused words and echoes, sticky glue sentences, dialogue-tag habits and readability drift across a chapter. It integrates with Scrivener – something Grammarly does not offer – which alone decides the question for many novelists. The interface asks more of you than Grammarly’s, and the free plan’s 500-word limit is a taster, not a tool.
How does the pricing really compare?
On annual billing the two are close: Grammarly Pro at $144/year against ProWritingAid Premium at $120/year. The story changes over time. ProWritingAid’s $399 lifetime licence breaks even against its own annual plan in a little over three years, and against Grammarly’s annual price in under three – after that, a working author’s editing software costs nothing. Grammarly has no lifetime route at any price. Students should also note ProWritingAid’s 20% student discount.
Which should you pick?
Pick Grammarly if your writing is emails, reports, applications and posts, and you want corrections everywhere with zero workflow change. Start free; upgrade to Pro for rewrites and plagiarism checks.
Pick ProWritingAid if you are revising a book, thesis or other long manuscript, write in Scrivener, or want the lifetime deal. Premium is the value pick; Premium Pro adds higher critique allowances for heavy revisers.
Bottom line: Grammarly polishes what you type today. ProWritingAid improves the writer over a manuscript. Short-form, go Grammarly; long-form, go ProWritingAid – some authors reasonably run both.
FAQ
Is ProWritingAid cheaper than Grammarly?
Slightly, on annual plans: $120/year versus $144/year. With the $399 lifetime licence, ProWritingAid becomes far cheaper over several years.
Does Grammarly work in Scrivener?
No native integration. ProWritingAid integrates directly with Scrivener, which is a major reason fiction writers choose it.
Which is better for a novel?
ProWritingAid. Its pacing, repetition and dialogue reports are built for manuscript revision, while Grammarly focuses on sentence-level correctness and tone.
Can I use Grammarly for free?
Yes. The free plan covers basic grammar, spelling and tone detection plus 100 AI prompts a month – enough for light everyday writing.