Grammarly vs Hemingway vs ProWritingAid: The Writing-Assistant Pricing Playbook

Three editors, three different things being sold

Grammarly, Hemingway Plus, and ProWritingAid promise better writing, but they sell three different products. Grammarly sells always-on correction plus a prompt allowance, per seat. Hemingway sells a metered allowance of AI sentence rewrites. ProWritingAid sells long-form editing reports and a manuscript toolkit, per writer, with a lifetime option no rival offers. Comparing only the headline monthly price picks the wrong tool, because the headline hides the meter: prompts for Grammarly, sentences for Hemingway, reports per day for ProWritingAid.

All prices come from the vendors' own pricing pages, read on 2026-11-10; any figure not from a vendor page is flagged corroborated-secondary.

The price cards, side by side

Grammarly lists three plans. Free costs $0 a month and covers spelling and grammar, tone, and 100 AI prompts a month. Pro costs $12 a month; the page's own plan data prices it at $144 for one year, $30 for one month, $60 for three months ($20 a month quarterly). Pro adds full-sentence rewrites, tone adjustment, fluency help, unlimited personalized suggestions, plagiarism and AI-generated-text detection, and 2,000 AI prompts per member a month, plus one style guide. Enterprise is contact sales, adding SAML single sign-on, SCIM, BYOK, and audit logs.

Hemingway Editor Plus prices by AI sentences. Individual 5K: $8.33 a month, billed as $100 a year, for 5,000 AI sentence rewrites a month. Individual 10K: $12.50 a month, billed as $150 a year, for 10,000. Team 10K costs $12.50 per user a month, billed as $150 per seat a year, for up to 50 users, with 10,000 sentences per user a month, a single bill, and admin roles. Enterprise is custom: 20,000 sentences per user a month, single sign-on. All Plus plans add unlimited grammar fixes, document review, eight tone styles, readability scoring. Trial: two weeks, no card, cancels automatically.

ProWritingAid prices by writer. Premium costs $30 a month billed monthly, $10 a month billed yearly ($120 a year), or $399 as a one-time lifetime payment. Premium Pro costs $36 a month billed monthly, $12 a month billed yearly ($144 a year), or $699 lifetime. Premium adds unlimited line-editing runs and rephrases, one chapter critique a day, 9 nudges, 5 sparks, 25+ analysis reports, a custom style guide and dictionary, author comparison, unlimited storage. Premium Pro raises the ceilings to 30 critiques, 15 nudges, 50 sparks a day, and adds live workshops, 200+ on-demand workshops, daily cowriting sprints.

What the free tier actually lets you do

Grammarly Free costs $0 and gives spelling and grammar correction, tone, and 100 AI prompts a month — about three a day. Short email only; rewrites, plagiarism, and AI detection sit behind Pro.

Hemingway's free tier is the web editor itself, free with no sign-up, plus free online grammar, paraphrase, proofreading, and readability checkers. The readability highlighting — adverbs, passive voice, hard sentences, grade level — is free. The AI costs money: rewrites, tone changes, and document review live in Plus, behind the two-week trial. A writer who only wants the readability pass never pays.

ProWritingAid Free is the most tightly rationed: 2 line-editing runs a day on up to 500 words each, 10 rephrases, 3 nudges, 3 sparks, and 3 Story Canvas runs a day, with grammar checking, a thesaurus, and 40+ document types. Two 500-word runs a day is 1,000 words of coverage: a short blog post, not a chapter. Our Perplexity vs ChatGPT vs Claude AI search pricing playbook applies the same test to search tools, where the meter is searches per day.

Plagiarism and AI detection: who includes it, who charges, who skips it

Grammarly Pro includes plagiarism detection and AI-generated-text detection in the $12 plan. For a team publishing client, student, or sponsored work, that removes a separate checker subscription.

ProWritingAid takes the opposite position. Its pricing page lists the Plagiarism Check as "Additional cost" on every tier, and links out to buy checks separately. A Premium subscriber who needs originality verification pays twice: once for the license and again per plagiarism check. The same page is silent on AI detection, so a buyer who needs to screen AI-generated text must budget a third tool.

Hemingway sells neither. Its Plus page lists AI sentence rewrites, grammar fixes, tone styles, document review, and readability scoring — no plagiarism checker or AI detector. Hemingway is a clarity editor, not a compliance tool: a newsroom or school that must prove originality cannot do it with Hemingway alone. The Midjourney vs DALL-E vs Stable Diffusion image generation pricing playbook makes the same point for image tools.

Worked example — the 5-seat editorial team on annual billing

Take a five-person editorial team that publishes every weekday and needs plagiarism screening on everything it ships, at the annual-billed rate: Grammarly Pro $12, Hemingway Team 10K $12.50, Premium $10, Premium Pro $12 a seat a month.

Premium is cheapest at $600 a year, $120 less than Grammarly Pro. But this team needs plagiarism screening, and ProWritingAid charges extra for every check while Grammarly includes it, so even a modest volume erases the $120 gap. The honest comparison is $600 plus an unknown add-on bill against $720 with plagiarism included. Grammarly Pro is the cheaper complete answer here.

Worked example — the solo novelist and the lifetime break-even

Now take a solo novelist with a 90,000-word manuscript who wants the deepest style reports. Hemingway Individual 5K at $100 a year gives 5,000 AI sentence rewrites a month — 60,000 a year, about 900,000 words at 15 words a sentence, far more than one manuscript needs, so the allowance is not the constraint. The constraint is report depth: Hemingway has no chapter critique, no manuscript analysis, and no style reports. Premium at $120 a year has all three, plus unlimited line-editing runs and rephrases. For this writer the comparison is $100 against $120, and the $20 buys the actual product: manuscript-level analysis.

ProWritingAid Premium lifetime costs $399 once. Against the $120 annual price, the break-even point is:

Four years of Premium on annual billing costs $480 against $399 once, saving $81; five years of Premium Pro $720 against $699, only $21. Lifetime is a good deal on Premium, marginal on Premium Pro, and only if the writer is certain to stay. The risk is lock-in: no refund after the 3-day guarantee, so if the writer switches tools in year two, the $399 is gone. An unsure writer should take the $120 annual plan for one year and decide with evidence.

The monthly cost math at 1, 5, and 25 seats

Grammarly Pro at $30 a month billed monthly costs $360 a year for one seat; on annual billing $144, saving $216, or 60 percent. Premium at $30 a month billed monthly also costs $360 a year; on annual billing $120, saving $240 — the 67 percent the pricing page advertises. Premium Pro at $36 a month billed monthly costs $432 a year; on annual billing $144, saving $288.

At 25 seats the spread is $750 a year: $3,000 for Premium against $3,750 for Hemingway Team 10K. One caution: ProWritingAid publishes no team plan, so 25 seats means 25 separate licenses with no single bill, no admin roles, and no central seat management, while Grammarly Pro and Hemingway Team bill per seat centrally.

Paying for the tool: the back office

The price card is only half the purchase. Pay by card and the charge lands as a SaaS subscription; Grammarly offers bank transfer (ACH/Wire) for annual purchases of 10 or more members. A US LLC, S-Corp, or C-Corp records the spend as a software expense against the vendor invoice; keep invoice, seat count, and renewal date together, because renewal is when seats drift from headcount. A non-US buyer wears the FX spread on every renewal, plus any IBAN/SWIFT wire fee. Contractors need a W-9 (US) or W-8BEN (non-US), with an EIN for the company and an SSN or ITIN for the individual.

Grammarly Enterprise lists GDPR controls, data loss prevention, and an audit logs API; Hemingway stores no documents and trains on none; ProWritingAid states 100% data security and privacy. Before buying, confirm storage, export, and whether the vendor's API or CSV export lets the team leave with its style guides. Track the spend like a B2B buyer: CAC and LTV belong to the vendor, but the buyer needs MRR discipline — the monthly recurring cost of the seat stack, reviewed quarterly against seats used. An unused seat is the most common waste here; the fix is a quarterly seat audit, not a cheaper tool.

Who should buy which

Buy Grammarly Pro if the work leaves the building: client copy, published articles, student submissions, or anything checked for originality. The plagiarism and AI-detection inclusion decides it, and the $12 annual seat is the middle price. Buy Hemingway Editor Plus if the problem is wordy, passive prose and the budget is one person: Individual 5K at $100 a year is the cheapest paid plan here, and the free web editor covers the readability pass. Buy the $19.99 one-time Classic desktop app only for the offline editor with no AI features; it is a different product from Plus, and the $19.99 buys no AI sentence allowance. Buy ProWritingAid Premium if the work is long-form: novels, memoirs, or dissertations that need chapter critiques, style reports, and a custom style guide. Buy Premium Pro only for the community and workshops; the toolkit is the same, and the $24 a year buys live sessions, not better editing.

The execution checklist

1. Step 1 — Name the failure. Plagiarism screening, wordy prose, or manuscript depth. The failure picks the tool; the price ranks the shortlist.
2. Step 2 — Run the free tier for two weeks. Grammarly Free, Hemingway's free editor, ProWritingAid Free.
3. Step 3 — Count the seats honestly. Paying seats only, not headcount. Remove leavers before renewal.
4. Step 4 — Price the annual bill. Annual-billed rate times 12 times seats. Compare that number, not the monthly headline.
5. Step 5 — Add the missing feature. If the tool lacks plagiarism checking, price a separate checker and add it to the annual total.
6. Step 6 — Check the billing period. Set annual billing on the first invoice. Diary the renewal date and the 3-day refund window.
7. Step 7 — Confirm the data terms. Storage, AI training, GDPR controls, CSV or API export.
8. Step 8 — Audit seats quarterly. Cancel unused seats at renewal; one costs $120 to $150 a year and buys nothing.

Grammarly Pro is the complete answer for teams that publish. Hemingway Plus is the cheapest way to fix wordy prose. ProWritingAid Premium is the deepest editor for long work, and the only one that can be bought once. Pick by the failure the tool removes, pay annually, audit the seats quarterly.