Grammarly vs 15Five

Side-by-side comparison to help you choose the best tool.

Grammarly

freemium

Productivity & Workflow

4.6 / 5.0

Grammarly is the world's most widely used AI writing assistant, providing grammar correction, style improvement, tone adjustment, and plagiarism detection across every platform where you write. GrammarlyGO adds generative AI for drafting, rewriting, and summarising. With 30M+ daily users and integrations in every major writing surface, Grammarly is the ubiquitous writing companion for professionals and students.

Best for: Everyone who writes professionally, wanting AI grammar assistance, tone guidance, and generative writing help across every platform they use

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15Five

paid

Productivity & Workflow

4.4 / 5.0

15Five is an HR performance management platform focused on continuous feedback, weekly check-ins, OKRs, and employee engagement. Its AI features include Spark AI for generating coaching recommendations, performance review summaries, and engagement data. Used by companies like Credit Karma, HubSpot, and Spotify, 15Five helps managers become better coaches through AI-guided data.

Best for: Companies focused on building a continuous feedback culture with AI coaching recommendations for managers

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Feature Comparison

Feature	Grammarly	15Five
Pricing	freemium	paid
Category	Productivity & Workflow	Productivity & Workflow
Rating	★★★★½ 4.6	★★★★☆ 4.4
Best For	Everyone who writes professionally, wanting AI grammar assistance, tone guidance, and generative writing help across every platform they use	Companies focused on building a continuous feedback culture with AI coaching recommendations for managers
Views	746	0

Pros & Cons — Grammarly

Pros

Most ubiquitous writing AI — works everywhere
GrammarlyGO adds generative capabilities
Tone suggestions are practically useful for professional comms

Cons

Premium features require subscription
Can be over-aggressive with suggestions

Pros & Cons — 15Five

Pros

Spark AI helps managers coach better with data
Weekly check-in format drives consistent feedback culture
Strong analytics for manager effectiveness

Cons

Narrower than full HCM platforms like Lattice
Some features require higher-tier plans

Key Features — Grammarly

Grammar, style & clarity corrections
GrammarlyGO generative AI
Tone detection & adjustment
Plagiarism checker
Integrations everywhere (email, docs, social)

Key Features — 15Five

Continuous feedback & weekly check-ins
Spark AI coaching recommendations
OKR & goal tracking
AI performance review summarisation
Engagement surveys & analytics

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