Grammarly vs ProWritingAid

Pricing, features, platforms and who each one suits — side by side.

Grammarly

AI writing assistant for grammar, tone, rewrites and AI-text detection

FreemiumVisit site

ProWritingAid

Grammar checking, line editing and story critique for fiction writers

FreemiumVisit site

Choose Grammarly if…

you work on iOS, Android
you're in its core audience: students, professionals

Choose ProWritingAid if…

you're in its core audience: novelists and fiction writers, self-published authors

Side by side

FeatureG

GrammarlyP

ProWritingAid

Pricing modelFreemiumFreemium

Starting price——

Free plan

Free trial

API

Open source

Trains AI on your contentYes, unless you opt outNo

Data retentionSaved documents kept until you delete them or your accountAnalysed text deleted after checking; only explicitly saved documents are kept

Security and complianceSOC 2 Type IIGDPR

AI rewrites

Tone adjustment—

Plagiarism checker

AI text detection—

Non-English checking—

Word/Google Docs add-in

Browser extension—

Custom style guide

PlatformsWeb, Windows, macOS, iOS, Android, ChromeWeb, macOS, Windows, Chrome

CategoryGrammar & ProofreadingGrammar & Proofreading

CompanySuperhuman Platform Inc.Orpheus Technology Ltd

Based inUnited StatesUnited Kingdom

Founded20092013

Part ofSuperhuman—

Key features

G Grammarly

Real-time spelling, grammar and clarity checks
Paragraph and full-sentence rewrites
Tone suggestions for different audiences
Reader Reactions predicts how readers respond
AI Detector and Humanizer agents
Plagiarism checker and citation generator
Works in MS Office, Google Docs and browsers
Enterprise style guides, brand tones and DLP

P ProWritingAid

Grammar, spelling and punctuation checker
25+ writing analysis reports
Rephrase tool for rewriting sentences
Chapter Critique and full manuscript analysis
Story Canvas and Outline Crafter for planning
Comparison of your writing style with 90 fiction authors
Integrations with Word, Google Docs, Scrivener and browsers
Custom style guide and dictionary

Plans and prices

From each vendor's site. Prices change — confirm before buying.

Grammarly

Free€0

Pro€12/member/mo billed annually (€30 billed monthly)

EnterpriseCustom

ProWritingAid

Free€0

Premium€30/mo monthly, €10/mo billed yearly (€120), or €399 lifetime

Premium Pro€36/mo monthly, €12/mo billed yearly (€144), or €699 lifetime

Strengths and limitations

Grammarly

Free plan includes grammar checks and 100 AI prompts a month
Available on desktop, mobile, browser extensions, MS Office and Google Docs
Pro includes plagiarism and AI-text detection
Enterprise offers SSO, SCIM, BYOK and data loss prevention

Pro costs €30 when billed monthly versus €12 billed annually
Free plan is limited to 100 AI prompts per month
Enterprise pricing is not published

ProWritingAid

Free plan with grammar checks and daily Rephrases
Lifetime purchase option on paid plans
Works in Word, Google Docs, Scrivener and major browsers
Discount available for students

Free plan analyzes only 500 words at a time
Supports English only
Monthly plans are not refundable, and the money-back guarantee on other plans lasts only 3 days
In-depth manuscript analysis needs separately purchased Story Credits